diff --git a/.github/workflows/php-syntax-check.yml b/.github/workflows/php-syntax-check.yml
index d31edbd99..55ed48b4a 100644
--- a/.github/workflows/php-syntax-check.yml
+++ b/.github/workflows/php-syntax-check.yml
@@ -14,7 +14,7 @@ jobs:
 
     steps:
       - name: Checkout code
-        uses: actions/checkout@v2
+        uses: actions/checkout@v4
 
       - name: Check PHP syntax
         run: |
diff --git a/docker/Dockerfile-php7 b/docker/Dockerfile-php7
deleted file mode 100644
index 45519042b..000000000
--- a/docker/Dockerfile-php7
+++ /dev/null
@@ -1,14 +0,0 @@
-FROM php:7.4-apache
-MAINTAINER craigk5n <craig@k5n.us>
-
-RUN docker-php-ext-install mysqli
-
-#COPY docker/cron-hourly /tmp/cron.hourly
-#RUN crontab /tmp/cron.hourly
-
-# Run the cron every hour
-#RUN echo '0 * * * * php /var/www/html/tools/send_reminders.php' > /etc/crontabs/root
-#TODO: setup cron
-
-#RUN chown -R www-data:www-data /var/www
-
diff --git a/docker/Dockerfile-php8 b/docker/Dockerfile-php8
index 9a962caf5..625e9f984 100644
--- a/docker/Dockerfile-php8
+++ b/docker/Dockerfile-php8
@@ -1,11 +1,9 @@
-#escape=`
-# To run on Windows, where \ is the path separator.
-
-FROM php:8.0-apache
-# MAINTAINER deprecated in favor of LABEL.
-LABEL craigk5n <craig@k5n.us>
-LABEL vendor "k5n.us"
+# Use the official PHP image with Apache
+FROM php:8-apache
+LABEL maintainer="craig@k5n.us"
+LABEL vendor="k5n.us"
 
+# Install mysqli extension
 RUN docker-php-ext-install mysqli
 
 # Copy all files except those in .dockerignore
@@ -15,3 +13,9 @@ COPY . /var/www/html/
 # to allow the web-based installer to update it.
 RUN touch /var/www/html/includes/settings.php
 RUN chmod 777 /var/www/html/includes/settings.php
+
+# Set working directory
+WORKDIR /var/www/html
+
+# Start Apache server in the foreground
+CMD ["apache2-foreground"]
diff --git a/docker/Dockerfile-php8-dev b/docker/Dockerfile-php8-dev
index 207f576cc..7a1576408 100644
--- a/docker/Dockerfile-php8-dev
+++ b/docker/Dockerfile-php8-dev
@@ -1,12 +1,21 @@
-FROM php:8.0-apache
-LABEL org.opencontainers.image.authors="craig@k5n.us"
+# Use the official PHP image with Apache
+FROM php:8-apache
+LABEL maintainer="craig@k5n.us"
+LABEL vendor="k5n.us"
+
+# Install mysqli extension
 RUN docker-php-ext-install mysqli
 
-#COPY docker/cron-hourly /tmp/cron.hourly
-#RUN crontab /tmp/cron.hourly
+# Install GD extension and its dependencies
+RUN apt-get update && apt-get install -y \
+        libfreetype6-dev \
+        libjpeg62-turbo-dev \
+        libpng-dev \
+    && docker-php-ext-configure gd --with-freetype --with-jpeg \
+    && docker-php-ext-install -j$(nproc) gd
 
-# Run the cron every hour
-#RUN echo '0 * * * * php /var/www/html/tools/send_reminders.php' > /etc/crontabs/root
-#TODO: setup cron
+# Set working directory
+WORKDIR /var/www/html
 
-#RUN chown -R www-data:www-data /var/www
+# Start Apache server in the foreground
+CMD ["apache2-foreground"]
diff --git a/docker/docker-compose-php7.yml b/docker/docker-compose-php7.yml
deleted file mode 100644
index 58d6c5cd3..000000000
--- a/docker/docker-compose-php7.yml
+++ /dev/null
@@ -1,44 +0,0 @@
-# The first time you run this, you will need to grant permission
-# for the webcalendar user to access mariadb (after you have run
-# docker-compose up).  You only need to do this once.
-#
-#   Start a shell on the mariadb container:
-#     docker-compose exec db /bin/sh
-#   Start the mariadb client:
-#     /bin/mariadb -p
-#     (enter the MYSQL_ROOT_PASSWORD below)
-#   Execute the following three db commands:
-#     GRANT ALL PRIVILEGES ON *.* TO webcalendar@localhost IDENTIFIED BY 'Webcalendar.1' WITH GRANT OPTION;
-#     FLUSH PRIVILEGES;
-#     QUIT
-
-version: '3.1'
-
-services:
-
-  db:
-    image: mariadb
-    container_name: webcalendar-db
-    volumes:
-      - mysql-data:/var/lib/mysql
-      - /etc/localtime:/etc/localtime:ro
-    environment:
-      - MYSQL_ROOT_PASSWORD=Webcalendar.1
-      - MYSQL_PASSWORD=Webcalendar.1
-      - MYSQL_DATABASE=webcalendar
-      - MYSQL_USER=webcalendar
-    restart: unless-stopped
-
-  webcalendar-php7:
-    build:
-      context: .
-      dockerfile: Dockerfile
-    depends_on:
-      - db
-    ports:
-      - 8080:80
-    volumes:
-      - .:/var/www/html/
-
-volumes:
-  mysql-data:
diff --git a/docker/docker-compose-php8-dev.yml b/docker/docker-compose-php8-dev.yml
index 85663f9ec..a9de423a3 100644
--- a/docker/docker-compose-php8-dev.yml
+++ b/docker/docker-compose-php8-dev.yml
@@ -1,9 +1,10 @@
+# Run docker-compose from the top-level WebCalendar directory and not from this "docker" subdirectory.
 # The first time you run this, you will need to grant permission
 # for the webcalendar user to access mariadb (after you have run
 # docker-compose up).  You only need to do this once.
 #
 #   Start a shell on the mariadb container:
-#     docker-compose -f docker-compose-php8.yml exec db /bin/sh
+#     docker-compose -f docker/docker-compose-php8-dev.yml exec db /bin/sh
 #   Start the mariadb client:
 #     /bin/mariadb -p
 #     (enter the MYSQL_ROOT_PASSWORD below)
@@ -14,7 +15,7 @@
 #
 #   If you need shell access on the webserver container running WebCalendar, you can use
 #   the following command:
-#     docker-compose -f docker-compose-php8.yml exec webcalendar-php8 /bin/sh
+#     docker-compose -f docker/docker-compose-php8-dev.yml exec webcalendar-php8 /bin/sh
 
 version: '3.1'
 
@@ -42,7 +43,7 @@ services:
     ports:
       - 8080:80
     volumes:
-      - .:/var/www/html/
+      - ..:/var/www/html/
 
 volumes:
   mysql-data:
diff --git a/docker/docker-compose-php8.yml b/docker/docker-compose-php8.yml
index 05373334f..1e8b13c1f 100644
--- a/docker/docker-compose-php8.yml
+++ b/docker/docker-compose-php8.yml
@@ -1,9 +1,10 @@
+# Run docker-compose from the top-level WebCalendar directory and not from this "docker" subdirectory.
 # The first time you run this, you will need to grant permission
 # for the webcalendar user to access mariadb (after you have run
 # docker-compose up).  You only need to do this once.
 #
 #   Start a shell on the mariadb container:
-#     docker-compose -f docker-compose-php8.yml exec db /bin/sh
+#     docker-compose -f docker/docker-compose-php8.yml exec db /bin/sh
 #   Start the mariadb client:
 #     /bin/mariadb -p
 #     (enter the MYSQL_ROOT_PASSWORD below)
@@ -14,7 +15,7 @@
 #
 #   If you need shell access on the webserver container running WebCalendar, you can use
 #   the following command:
-#     docker-compose -f docker-compose-php8.yml exec webcalendar-php8 /bin/sh
+#     docker-compose -f docker/docker-compose-php8.yml exec webcalendar-php8 /bin/sh
 
 version: '3.1'
 
diff --git a/includes/classes/Event.php b/includes/classes/Event.php
index cbebdd4f4..994ed8140 100644
--- a/includes/classes/Event.php
+++ b/includes/classes/Event.php
@@ -17,192 +17,141 @@
 class Event {
   /**
    * The event's name.
-   * @var string
-   * @access private
    */
-  var $_name;
+  private string $_name;
   /**
    * The event's description.
-   * @var string
-   * @access private
    */
-  var $_description;
+  private string $_description;
   /**
    * The event's date (in YYYYMMDD format).
-   * @var string
-   * @access private
    */
-  var $_date;
+  private string $_date;
   /**
    * The event's date in the local user's timezone
    */
-  var $_localDate;
+  private $_localDate;
   /**
    * The event's time (in HHMMSS format).
-   * @var string
-   * @access private
    */
-  var $_time;
+  private string $_time;
   /**
    * The event's time in local timezone (in HHMM format)
    */
-  var $_localTime;
+  private string $_localTime;
   /**
    * The event's modified date (in YYYYMMDD format).
-   * @var string
-   * @access private
    */
-  var $_moddate;
+  private string $_moddate;
   /**
    * The event's modified time (in HHMMSS format).
-   * @var string
-   * @access private
    */
-  var $_modtime;
+  private string $_modtime;
   /**
    * The event's ID.
-   * @var int
-   * @access private
    */
-  var $_id;
+  private int $_id;
   /**
    * Extension ID.
    *
    * If this event is an extension of an event that carried over into the
    * current date, <var>$_extForID</var> will hold the original event's date.
-   *
-   * @var mixed
-   * @access private
    */
-  var $_extForID;
+  private $_extForID;
   /**
    * The event's priority.
-   * @var int
-   * @access private
    */
-  var $_priority;
+  private int $_priority;
   /**
    * The event's access level.
-   * @var string
-   * @access private
    */
-  var $_access;
+  private string $_access;
   /**
    * The event's duration in minutes.
-   * @var int
-   * @access private
    */
-  var $_duration;
+  private int $_duration;
   /**
    * The event's status.
-   * @var string
-   * @access private
    */
-  var $_status;
+  private string $_status;
   /**
    * The event's owner.
-   * @var string
-   * @access private
    */
-  var $_owner;
+  private string $_owner;
   /**
    * The event's category ID.
-   * @var int
-   * @access private
    */
-  var $_category;
+  private string $_category;
   /**
-   *   Array of categories... not set by default.
+   * Array of categories... not set by default.
    * Must be set with setCategories first.
    */
-  var $_categories;
+  private $_categories;
   /**
    * The event's owner.
-   * @var mixed
-   * @access private
    */
-  var $_login;
+  private string $_login;
 
  /**
    * The event's type.
-   * @var mixed
-   * @access private
    */
-  var $_calType;
+  private $_calType;
  /**
    * The event's type name.
-   * @var mixed
-   * @access private
    */
-  var $_calTypeName;
+  private $_calTypeName;
  /**
    * The event's location.
    * @var mixed
    * @access private
    */
-  var $_location;
+  private $_location;
  /**
    * The event's url.
-   * @var mixed
-   * @access private
    */
-  var $_url;
+  private mixed $_url;
  /**
    * The event's dueDate.
-   * @var mixed
-   * @access private
    */
-  var $_dueDate;
+  private string $_dueDate;
  /**
    * The event's dueTime.
-   * @var mixed
-   * @access private
    */
-  var $_dueTime;
+  private $_dueTime;
+   /**
+   * The event's due date and time.
+   */
+  private string $_due;
  /**
    * The event's percent.
-   * @var mixed
-   * @access private
    */
-  var $_percent;
+  private $_percent;
 
   /**
    * The event's end time .
-   * @var mixed
-   * @access private
    */
-  var $_endTime;
+  private $_endTime;
  /**
    * The event's end datetime .
-   * @var mixed
-   * @access private
    */
-  var $_endDateTime;
+  private $_endDateTime;
  /**
    * Is this an All Day event?
-   * @var bool
-   * @access private
    */
-  var $_allDay;
+  private $_allDay;
  /**
    * Is this an Timed event?
-   * @var bool
-   * @access private
    */
-  var $_timed;
+  private $_timed;
  /**
    * Is this an Untimed event?
-   * @var bool
-   * @access private
    */
-  var $_untimed;
-
+  private $_untimed;
  /**
    * Flag to record a cloned event
-   * @var int
-   * @access private
    */
-  var $_clone;
+  private $_clone;
+
   /**
    * Creates a new Event.
    *
@@ -235,7 +184,6 @@ class Event {
   function __construct ( $name, $description, $date, $time, $id, $extForID,
           $priority, $access, $duration, $status, $owner, $category, $login,
           $calType, $location, $url, $dueDate, $dueTime, $percent, $moddate, $modtime ) {
-
     $this->_name = $name;
     $this->_description = $description;
     $this->_date = $date;
@@ -303,19 +251,21 @@ function getDate() {
     return $this->_date;
   }
 
-  function getDateTimeAdjusted() {
-    $year = substr ( $this->_date, 0, 4 );
-    $month = substr ( $this->_date, 4, 2 );
-    $day = substr ( $this->_date, 6, 2 );
-  if ( $this->isTimed() ) {
-    $h = (int) ( $this->_time / 10000 );
-    $m = ( $this->_time / 100 ) % 100;
-    $this->_Date = date ( 'Ymd', gmmktime ( $h, $m, 0, $month, $day, $year ) );
-  } else {
-   $h = $m = 0;
-   $this->_Date = date ( 'Ymd', mktime ( $h, $m, 0, $month, $day, $year ) );
-  }
-    return $this->_Date;
+  function getDateTimeAdjusted()
+  {
+    $year = substr($this->_date, 0, 4);
+    $month = substr($this->_date, 4, 2);
+    $day = substr($this->_date, 6, 2);
+    $ret = null;
+    if ($this->isTimed()) {
+      $h = (int) ($this->_time / 10000);
+      $m = ($this->_time / 100) % 100;
+      $ret = date('Ymd', gmmktime($h, $m, 0, $month, $day, $year));
+    } else {
+      $h = $m = 0;
+      $ret = date('Ymd', mktime($h, $m, 0, $month, $day, $year));
+    }
+    return $ret;
   }
   /**
    * Gets the event's time
@@ -402,8 +352,7 @@ function getDueDateTimeTS() {
    */
   function getDateTime() {
     $time = ($this->_time > 0? $this->_time: 0);
-    $this->_DateTime = $this->_date . sprintf ( "%06d", $time );
-    return $this->_DateTime;
+    return $this->_date . sprintf ( "%06d", $time );
   }
 
     /**
@@ -413,19 +362,21 @@ function getDateTime() {
    *
    * @access public
    */
-  function getDateTimeTS() {
-    $year = substr ( $this->_date, 0, 4 );
-    $month = substr ( $this->_date, 4, 2 );
-    $day = substr ( $this->_date, 6, 2 );
-  if ( $this->isTimed() ) {
-    $h = (int) ( $this->_time / 10000 );
-    $m = ( $this->_time / 100 ) % 100;
-    $this->_DateTime = gmmktime ( $h, $m, 0, $month, $day, $year );
-  } else {
-   $h = $m = 0;
-   $this->_DateTime = mktime ( $h, $m, 0, $month, $day, $year );
-  }
-    return $this->_DateTime;
+  function getDateTimeTS()
+  {
+    $ret = null;
+    $year = substr($this->_date, 0, 4);
+    $month = substr($this->_date, 4, 2);
+    $day = substr($this->_date, 6, 2);
+    if ($this->isTimed()) {
+      $h = (int) ($this->_time / 10000);
+      $m = ($this->_time / 100) % 100;
+      $ret = gmmktime($h, $m, 0, $month, $day, $year);
+    } else {
+      $h = $m = 0;
+      $ret = mktime($h, $m, 0, $month, $day, $year);
+    }
+    return $ret;
   }
 
   /**
diff --git a/includes/config.php b/includes/config.php
index 825ea5c33..1d4d07c65 100644
--- a/includes/config.php
+++ b/includes/config.php
@@ -191,9 +191,17 @@ function do_config($callingFromInstall=false)
         }
       }
     }
+  } else if (!file_exists(__DIR__ . '/settings.php') && !$callingFromInstall) {
+    // Redirect to installer
+    if (file_exists(__DIR__ . '/../install/index.php')) {
+      header('Location: install/index.php');
+      exit;
+    } else {
+      die_miserable_death(translate('Could not find settings.php file...'));
+    }
   } else {
     // Load from settings.php file
-    $settings_content = file_get_contents(__DIR__ . '/settings.php');
+    $settings_content = @file_get_contents(__DIR__ . '/settings.php');
     if (empty($settings_content)) {
       if ($callingFromInstall) {
         return; // not an error during install
@@ -228,11 +236,10 @@ function do_config($callingFromInstall=false)
   }
 
   // Extract db settings into global vars.
-  $db_database = $settings['db_database'];
-  $db_host     = $settings['db_host'];
-  $db_login    = $settings['db_login'];
-  $db_password = (empty($settings['db_password'])
-    ? '' : $settings['db_password']);
+  $db_database = $settings['db_database'] ?? '';
+  $db_host     = $settings['db_host'] ?? '';
+  $db_login    = $settings['db_login'] ?? '';
+  $db_password = $settings['db_password'] ?? '';
   $db_persistent = (preg_match(
     '/(1|yes|true|on)/i',
     $settings['db_persistent']
@@ -241,7 +248,7 @@ function do_config($callingFromInstall=false)
     '/(1|yes|true|on)/i',
     $settings['db_debug']
   ) ? true : false);
-  $db_type = $settings['db_type'];
+  $db_type = $settings['db_type'] ?? '';
 
   // If no db settings, then user has likely started install but not yet
   // completed. So, send them back to the install script.
@@ -346,7 +353,7 @@ function do_config($callingFromInstall=false)
         // (only an option when there are no database schema changes between
         // the version and the new version.)
         if (upgrade_requires_db_changes($db_type, $versionInDb, $PROGRAM_VERSION)) {
-          header($locateStr . $versionInDb);
+          header($locateStr);
           exit;
         } else {
           // We can just update the version in the database and move on.
diff --git a/includes/dbi4php.php b/includes/dbi4php.php
index 7e4412115..354a83c93 100644
--- a/includes/dbi4php.php
+++ b/includes/dbi4php.php
@@ -571,89 +571,103 @@ function dbi_get_blob( $table, $column, $key ) {
  *
  * @return bool True on success
  */
-function dbi_free_result( $res ) {
-  if( $res === true ) // Not needed for UPDATE, DELETE, etc
-    return;
+function dbi_free_result($res)
+{
+  if ($res === true) { // Not needed for UPDATE, DELETE, etc.
+    return true;
+  }
 
-  if( strcmp( $GLOBALS['db_type'], 'ibase' ) == 0 )
-    return ibase_free_result( $res );
-  elseif( strcmp( $GLOBALS['db_type'], 'ibm_db2' ) == 0 )
-    return db2_free_result( $res );
-  elseif( strcmp( $GLOBALS['db_type'], 'mysqli' ) == 0 )
-    return mysqli_free_result( $res );
-  elseif( strcmp( $GLOBALS['db_type'], 'odbc' ) == 0 )
-    return odbc_free_result( $res );
-  elseif( strcmp( $GLOBALS['db_type'], 'oracle' ) == 0 ) {
-    // Not supported. Ingore.
-    if( $GLOBALS['oracle_statement'] >= 0 ) {
-      OCIFreeStatement( $GLOBALS['oracle_statement'] );
-      $GLOBALS['oracle_statement'] = -1;
-    }
-  } elseif( strcmp( $GLOBALS['db_type'], 'postgresql' ) == 0 )
-    return pg_freeresult( $res );
-  elseif( strcmp( $GLOBALS['db_type'], 'sqlite' ) == 0 ) {
-    // Not supported
+  $dbType = $GLOBALS['db_type'] ?? 'undefined';
+  switch ($dbType) {
+    case 'ibase':
+      return ibase_free_result($res);
+    case 'ibm_db2':
+      return db2_free_result($res);
+    case 'mysqli':
+      return mysqli_free_result($res);
+    case 'odbc':
+      return odbc_free_result($res);
+    case 'oracle':
+      if ($GLOBALS['oracle_statement'] >= 0) {
+        OCIFreeStatement($GLOBALS['oracle_statement']);
+        $GLOBALS['oracle_statement'] = -1;
+      }
+      return true; // Assuming a successful operation as it's not directly supported.
+    case 'postgresql':
+      return pg_freeresult($res);
+    case 'sqlite':
+      // Not supported for SQLite, just return true.
+      return true;
+    case 'sqlite3':
+      // Not needed for SQLite3, just return true.
+      return true;
+    case 'undefined':
+      dbi_fatal_error('dbi_free_result(): ' . translate('db_type not defined.'));
+      break;
+    default:
+      dbi_fatal_error('dbi_free_result(): ' . translate('Unsupported db_type.') . ' (' . htmlentities($dbType) . ')');
+      break;
   }
-  elseif( strcmp( $GLOBALS['db_type'], 'sqlite3' ) == 0 ) {
-    // Not needed
-  } else
-    dbi_fatal_error( 'dbi_free_result(): '
-       . translate( 'db_type not defined.' ) );
 }
 
-/**
- * Gets the latest database error message.
- *
- * @return string The text of the last database error. (The type of information
- *                varies depending on which type of database is being used.)
- */
-function dbi_error() {
-  if( strcmp( $GLOBALS['db_type'], 'ibase' ) == 0 )
-    $ret = ibase_errmsg();
-  elseif( strcmp( $GLOBALS['db_type'], 'ibm_db2' ) == 0 ) {
-    $ret = db2_conn_errormsg();
 
-    if( $ret == '' )
-      $ret = db2_stmt_errormsg();
-  } elseif (strcmp($GLOBALS['db_type'], 'mysqli') == 0) {
-    if (!empty($GLOBALS['db_connection_info']['last_error'])) {
-      $ret = $GLOBALS['db_connection_info']['last_error'];
-    } else {
-      $ret = $GLOBALS['db_connection']->error;
-    }
-  } elseif( strcmp( $GLOBALS['db_type'], 'odbc' ) == 0 )
-    // No way to get error from ODBC API.
-    $ret = translate( 'Unknown ODBC error.' );
-  elseif( strcmp( $GLOBALS['db_type'], 'oracle' ) == 0 ) {
-    $e = OCIError( $GLOBALS['oracle_connection']
-      ? $GLOBALS['oracle_connection'] : '' );
-    $ret = htmlentities( $e['message'] );
-  } elseif( strcmp( $GLOBALS['db_type'], 'postgresql' ) == 0 )
-    $ret = pg_errormessage( $GLOBALS['postgresql_connection'] );
-  elseif( strcmp( $GLOBALS['db_type'], 'sqlite' ) == 0 ) {
-    if( empty( $GLOBALS['db_sqlite_error_str'] ) ) {
-      $ret = sqlite_last_error( $GLOBALS['sqlite_c'] );
-    } else {
-      $ret = $GLOBALS['db_sqlite_error_str'];
-      $GLOBALS['db_sqlite_error_str'] = '';
-    }
-  } elseif ( strcmp ( $GLOBALS['db_type'], 'sqlite3' ) == 0 ) {
-    try {
-      if ( empty($$GLOBALS['sqlite3_c']) || !empty($GLOBALS['db_sqlite_error_str'])) {
-        $ret = $GLOBALS['db_sqlite_error_str'];
+function dbi_error()
+{
+  $dbType = $GLOBALS['db_type'] ?? 'undefined';
+
+  switch ($dbType) {
+    case 'ibase':
+      return ibase_errmsg();
+
+    case 'ibm_db2':
+      $ret = db2_conn_errormsg();
+      return ($ret == '') ? db2_stmt_errormsg() : $ret;
+
+    case 'mysqli':
+      if (!empty($GLOBALS['db_connection_info']['last_error'])) {
+        return $GLOBALS['db_connection_info']['last_error'];
       } else {
-        $ret = $GLOBALS['sqlite3_c']->lastErrorMsg ();
+        return $GLOBALS['db_connection']->error;
       }
-    } catch ( Exception $e) {
-      $GLOBALS['db_sqlite_error_str'] = $e->getMessage();
-      $ret = $e->getMessage();
-    }
-  } else
-    $ret = 'dbi_error(): ' . translate( 'db_type not defined.' );
 
-  return ( strlen( $ret ) ? $ret : translate( 'Unknown error.' ) );
+    case 'odbc':
+      return translate('Unknown ODBC error.');
+
+    case 'oracle':
+      $e = OCIError($GLOBALS['oracle_connection'] ? $GLOBALS['oracle_connection'] : '');
+      return htmlentities($e['message']);
+
+    case 'postgresql':
+      return pg_errormessage($GLOBALS['postgresql_connection']);
+
+    case 'sqlite':
+      if (empty($GLOBALS['db_sqlite_error_str'])) {
+        return sqlite_last_error($GLOBALS['sqlite_c']);
+      } else {
+        return $GLOBALS['db_sqlite_error_str'];
+      }
+
+    case 'sqlite3':
+      try {
+        if (empty($GLOBALS['sqlite3_c']) || !empty($GLOBALS['db_sqlite_error_str'])) {
+          return $GLOBALS['db_sqlite_error_str'];
+        } else {
+          return $GLOBALS['sqlite3_c']->lastErrorMsg();
+        }
+      } catch (Exception $e) {
+        $GLOBALS['db_sqlite_error_str'] = $e->getMessage();
+        return $e->getMessage();
+      }
+
+    case 'undefined':
+      return 'dbi_error(): ' . translate('db_type not defined.');
+
+    default:
+      return 'dbi_error(): ' . translate('Unsupported db_type.') . ' (' . htmlentities($dbType) . ')';
+  }
 }
 
+
 /**
  * Displays a fatal database error and aborts execution.
  *
diff --git a/install/index.php b/install/index.php
index b9edf2584..5d644dbb8 100644
--- a/install/index.php
+++ b/install/index.php
@@ -230,6 +230,7 @@ function_exists('gd_info'),
 $databaseExists = false;
 $databaseCurrent = false;
 $settingsSaved = true; // True if a valid settings.php found unless user changes settings
+$detectedDbVersion = 'Unknown';
 if ($canConnectDb) {
     $reportedDbVersion = getDbVersion();
     $detectedDbVersion = getDatabaseVersionFromSchema();
@@ -381,7 +382,11 @@ function_exists('gd_info'),
         <?php
         // Get status for each step
         $settingsStorage = getenv('WEBCALENDAR_USE_ENV') ? translate("Environment variables") : "includes/settings.php";
-        $dbConnectionStatus = $canConnectDb ? "Can connect" : ("Cannot connect" . (empty($connectError) ? "" : ": " . $connectError));
+        if (empty($_SESSION['db_type'])) {
+            $dbConnectionStatus = translate('Unknown');
+        } else {
+            $dbConnectionStatus = $canConnectDb ? "Can connect" : ("Cannot connect" . (empty($connectError) ? "" : ": " . $connectError));
+        }
         $setupVersion = $PROGRAM_VERSION;
         $phpVersionStatus = (version_compare(phpversion(), '8.0', '>=')) ? "Supported" : "Not supported";
         ?>
diff --git a/install/install_appsettings.php b/install/install_appsettings.php
index 780467787..1e40da88e 100644
--- a/install/install_appsettings.php
+++ b/install/install_appsettings.php
@@ -202,6 +202,6 @@ function handlePulldownUpdate() {
         printNextPageButton($action);
     }
 } else {
-    printSubmitButton($action, $html, $buttonLabel);
+    printSubmitButton($action, $html ?? null, $buttonLabel ?? null);
 }
 ?>
\ No newline at end of file
diff --git a/install/install_appsettings_handler.php b/install/install_appsettings_handler.php
index fea01fc7c..e7200e3b5 100644
--- a/install/install_appsettings_handler.php
+++ b/install/install_appsettings_handler.php
@@ -1,38 +1,44 @@
 <?php
+$appSettingsCorrect = false;
 $app_settings = ['readonly', 'single_user', 'use_http_auth', 'user_inc', 'mode'];
 if ($usingEnv) {
   // This shouldn't happen.
   $error = translate('Unknown error');
 } else {
-  // Should not be getting here...
-  if ($appSettingsCorrect) {
-    // Save settings to session
-    $_SESSION['use_http_auth'] == 'N'; // default
-    $_SESSION['user_inc'] = $_POST['user_inc'];
-    if ($_SESSION['user_inc'] == 'http') {
-      $_SESSION['user_inc'] == 'user.php';
-      $_SESSION['use_http_auth'] == 'Y';
-    } else if ($_SESSION['user_inc'] == 'none') {
-      $_SESSION['user_inc'] == 'user.php'; // single-user
-    }
-    $_SESSION['single_user'] = $_POST['user_inc'] == 'none' ? 'Y' : 'N';
+  // Save settings to session
+  $_SESSION['use_http_auth'] == 'N'; // default
+  $_SESSION['user_inc'] = $_POST['user_inc'];
+  if ($_SESSION['user_inc'] == 'http') {
+    $_SESSION['user_inc'] == 'user.php';
+    $_SESSION['use_http_auth'] == 'Y';
+  } else if ($_SESSION['user_inc'] == 'none') {
+    $_SESSION['user_inc'] == 'user.php'; // single-user
+  }
+  $_SESSION['single_user'] = $_POST['user_inc'] == 'none' ? 'Y' : 'N';
+  if (empty($_POST['readonly']))
+    $_SESSION['readonly']  = 'N';
+  else
     $_SESSION['readonly'] = $_POST['readonly'] == '1' ? 'Y' : 'N';
-    $_SESSION['mode'] = $_POST['mode'];
-    $_SESSION['single_user_login'] = $_POST['single_user_login'];
-    // echo "<pre>"; print_r($_SESSION); echo "</pre>"; exit;
-    // Did the user change anything
-    $foundChange = false;
-    foreach ($app_settings as $setting) {
-      if ($_SESSION[$setting] != $settings[$setting] ){
-        $foundChange = true;
-      }
-    }
-    if ($foundChange) {
-      // Require user to save and overwrite settings.php in a future step.
-      $_SESSION['appSettingsModified'] = 1;
+  $_SESSION['mode'] = $_POST['mode'];
+  $_SESSION['single_user_login'] = $_POST['single_user_login'];
+  // echo "<pre>"; print_r($_SESSION); echo "</pre>"; exit;
+  // Did the user change anything
+  $foundChange = false;
+  foreach ($app_settings as $setting) {
+    if (empty($settings[$setting]) || $_SESSION[$setting] != $settings[$setting]) {
+      $foundChange = true;
     }
-    redirectToNextAction();
-  } else {
-    $error = translate('Invalid Application Settings');
   }
+  if ($foundChange) {
+    // Require user to save and overwrite settings.php in a future step.
+    $_SESSION['appSettingsModified'] = 1;
+  }
+  $appSettingsCorrect = isset($_SESSION['readonly']) && isset($_SESSION['user_inc']) &&
+    isset($_SESSION['use_http_auth']) && isset($_SESSION['single_user'])
+    && isset($_SESSION['mode']);
+}
+if ($appSettingsCorrect) {
+  redirectToNextAction();
+} else {
+  $error = translate('Invalid Application Settings');
 }
diff --git a/install/install_auth_handler.php b/install/install_auth_handler.php
index 642a09912..cadc6cd6c 100644
--- a/install/install_auth_handler.php
+++ b/install/install_auth_handler.php
@@ -1,35 +1,45 @@
 <?php
 
-function update_password_in_settings($file, $password, $hint) {
-    // Check if file exists
-    if (!file_exists($file)) {
-        return false; // File doesn't exist
-    }
+function update_password_in_settings($file, $password, $hint)
+{
+  // Check if file exists
+  if (!file_exists($file)) {
+    return false; // File doesn't exist
+  }
 
-    // Read the file content
-    $content = file_get_contents($file);
+  // Read the file content
+  $content = file_get_contents($file);
 
-    // Update or set the install_password and hint lines
-    if (strpos($content, 'install_password:') !== false) {
-        // Replace existing install_password and hint
-        $content = preg_replace('/install_password:.*\n/', 'install_password: ' . $password . "\n", $content);
-    } else {
-        // Add the install_password
-        $content = str_replace("# end settings.php", "install_password: " . $password . "\n# end settings.php", $content);
-    }
-    if (strpos($content, 'install_password_hint:') !== false) {
-        $content = preg_replace('/install_password_hint:.*\n/', 'install_password_hint: ' . $hint . "\n", $content);
-    } else {
-        $content = str_replace("# end settings.php", "install_password_hint: " . $hint . "\n# end settings.php", $content);
-    }
+  // Update or set the install_password and hint lines
+  if (strpos($content, 'install_password:') !== false) {
+    // Replace existing install_password and hint
+    $content = preg_replace('/install_password:.*\n/', 'install_password: ' . $password . "\n", $content);
+  } else {
+    // Add the install_password
+    $content = str_replace("# end settings.php", "install_password: " . $password . "\n# end settings.php", $content);
+  }
+  if (strpos($content, 'install_password_hint:') !== false) {
+    $content = preg_replace('/install_password_hint:.*\n/', 'install_password_hint: ' . $hint . "\n", $content);
+  } else {
+    $content = str_replace("# end settings.php", "install_password_hint: " . $hint . "\n# end settings.php", $content);
+  }
 
-    // Update the date
-    $date = new DateTime();
-    $formattedDate = $date->format('D, d M Y H:i:s O');
-    $content = preg_replace('/updated via install\/index.php on .*/', 'updated via install/index.php on ' . $formattedDate, $content);
+  // Update the date
+  $date = new DateTime();
+  $formattedDate = $date->format('D, d M Y H:i:s O');
+  $content = preg_replace('/updated via install\/index.php on .*/', 'updated via install/index.php on ' . $formattedDate, $content);
 
-    // Write the updated content back to the file
-    return file_put_contents($file, $content);
+  // Write the updated content back to the file
+  return file_put_contents($file, $content);
+}
+
+function write_password_in_new_settings($file, $password, $hint)
+{
+  $date = new DateTime();
+  $formattedDate = $date->format('D, d M Y H:i:s O');
+  $content = "<?php\n/* updated via install\/index.php on " . $formattedDate . "\n" .
+    "install_password: $password\ninstall_password_hint: $hint\n# end settings.php *\n/?>\n";
+  return file_put_contents($file, $content);
 }
 
 // Handle form submission on Auth page (both setting and checking password)
@@ -43,9 +53,14 @@ function update_password_in_settings($file, $password, $hint) {
     $error = translate('Your passwords must match.');
   }
   $hint = $_POST['hint'];
-  $ret = update_password_in_settings(__DIR__ . '/../includes/settings.php', md5($password), $hint);
-  if (! $ret) {
-    $error = 'Error writing includes/settings.php file.';
+  $settingsFile = __DIR__ . '/../includes/settings.php';
+  if (file_exists($settingsFile) && strlen(file_get_contents($settingsFile) > 10)) {
+    $ret = update_password_in_settings($settingsFile, md5($password), $hint);
+  } else {
+    $ret = write_password_in_new_settings($settingsFile, md5($password), $hint);
+  }
+  if (!$ret) {
+    $error = 'Error writing ' . $settingsFile . ' file.';
   } else {
     redirectToNextAction();
   }
@@ -62,4 +77,3 @@ function update_password_in_settings($file, $password, $hint) {
     $error = translate("Invalid passphrase.");
   }
 }
-?>
diff --git a/install/install_dbload_handler.php b/install/install_dbload_handler.php
index 9adfe11eb..7c5aa3bb9 100644
--- a/install/install_dbload_handler.php
+++ b/install/install_dbload_handler.php
@@ -110,8 +110,6 @@ function createDB2Database($hostname, $login, $password, $databaseName): bool
   return true;
 }
 
-
-
 try {
   switch ($_SESSION['db_type']) {
     case 'mysqli':
diff --git a/install/install_dbsettings.php b/install/install_dbsettings.php
index e0ca704f5..5523d5c2e 100644
--- a/install/install_dbsettings.php
+++ b/install/install_dbsettings.php
@@ -43,7 +43,7 @@ function printDbSetting($name)
                     list($checkType, $checkValue) = explode(':', $value);
                     $isSupported = ($checkType === 'function') ? @function_exists($checkValue) : @class_exists($checkValue);
                     ?>
-                    <option value="<?= $type; ?>" <?= ($type == $_SESSION['db_type']) ? 'selected' : ''; ?> <?= (!$isSupported) ? 'disabled' : ''; ?> title="<?= (!$isSupported) ? 'Required PHP module not available' : ''; ?>">
+                    <option value="<?= $type; ?>" <?= (isset($_SESSION['db_type']) && $type == $_SESSION['db_type']) ? 'selected' : ''; ?> <?= (!$isSupported) ? 'disabled' : ''; ?> title="<?= (!$isSupported) ? 'Required PHP module not available' : ''; ?>">
                         <?= ucfirst($type); ?>
                     </option>
                 <?php endforeach; ?>
diff --git a/install/install_dbsettings_handler.php b/install/install_dbsettings_handler.php
index ecc6cb0be..bcf479b93 100644
--- a/install/install_dbsettings_handler.php
+++ b/install/install_dbsettings_handler.php
@@ -27,6 +27,7 @@
     }
     if (!empty($value)) {
         $fileContent .= "$key: $value\n";
+        $_SESSION[$key] = $value;
     }
 }
 
diff --git a/install/install_dbtables.php b/install/install_dbtables.php
index 421c91bd7..f1b1a6de1 100644
--- a/install/install_dbtables.php
+++ b/install/install_dbtables.php
@@ -5,6 +5,7 @@
   //$detectedDbVersion = "v1.1.2";
   //$databaseCurrent = false;
   $sql = '';
+  $buttonLabel = translate('Upgrade Database');
   if ($databaseCurrent) {
     $msg = translate("Your XXX database named 'YYY' is up to date.  You may go on to the next step.");
     $msg = str_replace('XXX', $_SESSION['db_type'], $msg);
@@ -17,6 +18,7 @@
       $msg = str_replace('YYY', $_SESSION['db_database'], $msg);
       $sqlFile = getSqlFile($_SESSION['db_type'], false);
       $sql = extractSqlCommandsFromFile($sqlFile);
+      $buttonLabel = translate('Create Database');
     } else {
       $msg = translate("Your XXX database named 'YYY' needs upgrading from version ZZZ.");
       $msg = str_replace('XXX', $_SESSION['db_type'], $msg);
@@ -40,7 +42,7 @@
 ?>
   <button type="button" id="displaySqlBtn" class="btn btn-info" data-toggle="modal" data-target="#sqlModal"><?php etranslate('Display SQL'); ?></button>
 <?php
-  printSubmitButton($action, null, translate('Upgrade Database'));
+  printSubmitButton($action, null, $buttonLabel);
 }
 ?>
 
diff --git a/install/install_dbtables_handler.php b/install/install_dbtables_handler.php
index 03d5d767e..b98fed423 100644
--- a/install/install_dbtables_handler.php
+++ b/install/install_dbtables_handler.php
@@ -39,7 +39,7 @@
 try {
   $success = true;
   if (empty($error)) {
-    if ($emptyDb) {
+    if ($emptyDatabase) {
       executeSqlFromFile($install_filename);
     } else {
       if (empty($detectedDbVersion) || $detectedDbVersion == 'Unknown') {
diff --git a/install/install_functions.php b/install/install_functions.php
index 04334c20b..81977d6bf 100644
--- a/install/install_functions.php
+++ b/install/install_functions.php
@@ -313,12 +313,12 @@ function do_v1_9_11_updates()
         $base64Data = base64_encode($iconData);
         // Create a data URL.
         $dataUrl = 'data:image/png;base64,' . $base64Data;
-        echo '<img src="' . $dataUrl . '" alt="Embedded Image"> <br>';
-        echo "cat $catId done <br>\n";
+        //echo '<img src="' . $dataUrl . '" alt="Embedded Image"> <br>';
+        //echo "cat $catId done <br>\n";
         // Delete the files so we don't repeat this later
-        //if (!unlink($iconFile)) {
-        //  echo "Failed to delete icon file $iconFile";
-        //}
+        if (!unlink($iconFile)) {
+          echo "Failed to delete icon file $iconFile";
+        }
       }
     }
   }
@@ -487,7 +487,7 @@ function getDatabaseVersionFromSchema($silent = true)
   global $database_upgrade_matrix, $PROGRAM_VERSION, $settings, $show_all_errors;
   $dbVersion = null;
   $success = true;
-  //$silent = false;
+  $silent = true;
 
   // Suppress errors based on $show_all_errors.
   if (!$show_all_errors)
@@ -514,6 +514,9 @@ function getDatabaseVersionFromSchema($silent = true)
         // could have worked on.
         $res = false;
         $success = false;
+        if (!$silent) {
+          echo "Failed at: $sql <br>";
+        }
       }
       if ($res) {
         if (!$silent) {
@@ -627,6 +630,7 @@ function executeSqlFromFile($filename)
   foreach ($sqlStatements as $statement) {
     if (!empty($statement)) {
       // Assuming dbi_execute() is a function that takes a SQL statement and executes it
+      echo "Statement: $statement <br>";
       dbi_execute($statement);
     }
   }
diff --git a/install/sql/tables-db2.sql b/install/sql/tables-db2.sql
index cbefb53ab..e13f6336d 100644
--- a/install/sql/tables-db2.sql
+++ b/install/sql/tables-db2.sql
@@ -156,7 +156,7 @@ CREATE TABLE webcal_categories (
   cat_status CHAR DEFAULT 'A',
   cat_icon_mime VARCHAR(32) DEFAULT NULL,
   cat_icon_blob BLOB DEFAULT NULL,
-  PRIMARY KEY (cal_id, cat_id, cat_order, cat_owner)
+  PRIMARY KEY (cat_id, cat_order, cat_owner)
 );
 CREATE TABLE webcal_asst (
   cal_boss VARCHAR(25) NOT NULL,
diff --git a/install/sql/tables-mysql.sql b/install/sql/tables-mysql.sql
index 72ed8e7e3..62e95f8e5 100644
--- a/install/sql/tables-mysql.sql
+++ b/install/sql/tables-mysql.sql
@@ -432,7 +432,7 @@ CREATE TABLE webcal_categories (
   cat_icon_mime VARCHAR(32) DEFAULT NULL,
   /* category icon image blob */
   cat_icon_blob LONGBLOB DEFAULT NULL,
-  PRIMARY KEY ( cal_id, cat_id, cat_order, cat_owner )
+  PRIMARY KEY ( cat_id, cat_owner )
 );
 
 /**
diff --git a/install/sql/tables-oracle.sql b/install/sql/tables-oracle.sql
index 4cc134af7..5a4c30b59 100644
--- a/install/sql/tables-oracle.sql
+++ b/install/sql/tables-oracle.sql
@@ -159,7 +159,7 @@ CREATE TABLE webcal_categories (
   cat_status CHAR DEFAULT 'A',
   cat_icon_mime VARCHAR(32) DEFAULT NULL,
   cat_icon_blob BLOB DEFAULT NULL,
-  PRIMARY KEY ( cal_id, cat_id, cat_order, cat_owner )
+  PRIMARY KEY ( cat_id, cat_order, cat_owner )
 );
 CREATE TABLE webcal_asst (
   cal_boss VARCHAR2(25) NOT NULL,
diff --git a/install/sql/tables-postgres.sql b/install/sql/tables-postgres.sql
index 58412cff5..6caa5889e 100644
--- a/install/sql/tables-postgres.sql
+++ b/install/sql/tables-postgres.sql
@@ -158,7 +158,7 @@ CREATE TABLE webcal_categories (
   cat_status CHAR DEFAULT 'A',
   cat_icon_mime VARCHAR(32) DEFAULT NULL,
   cat_icon_blob BYTEA DEFAULT NULL,
-  PRIMARY KEY ( cal_id, cat_id, cat_order, cat_owner )
+  PRIMARY KEY ( cat_id, cat_order, cat_owner )
 );
 CREATE TABLE webcal_asst (
   cal_boss VARCHAR(25) NOT NULL,
diff --git a/install/sql/upgrade_matrix.php b/install/sql/upgrade_matrix.php
index dfa3403d8..221c9869e 100644
--- a/install/sql/upgrade_matrix.php
+++ b/install/sql/upgrade_matrix.php
@@ -36,7 +36,7 @@
   ['INSERT INTO webcal_nonuser_cals ( cal_login, cal_admin, cal_url ) VALUES ( "zzz", "zzz", "zzz" )',
    'DELETE FROM webcal_nonuser_cals WHERE cal_login = "zzz"',
    'v1.1.0e-CVS', 'upgrade_v1.1.1'],
-  ['INSERT INTO webcal_categories ( cat_id, cat_name, cat_color ) VALUES ( "999", "zzz", "#FFFFFF" )',
+  ['INSERT INTO webcal_categories ( cat_id, cat_name, cat_color, cat_owner ) VALUES ( "999", "zzz", "#FFFFFF", "nobody" )',
    'DELETE FROM webcal_categories WHERE cat_id = 999',
    'v1.1.1', 'upgrade_v1.1.2'],
   // Upgrade from 1.1.2 -> 1.3.0
diff --git a/view_entry.php b/view_entry.php
index 9df2d6250..c098ac61e 100644
--- a/view_entry.php
+++ b/view_entry.php
@@ -893,9 +893,9 @@
 else {
     echo '
   ' . $num_comment . ' ' . translate('comments') . '
-  <button class="btn" id="showbutton" type="button" onclick="showComments();">'
+  <button class="btn btn-secondary" id="showbutton" type="button" onclick="showComments();">'
     . translate('Show') . '</button>'
-    . '<button class="btn" id="hidebutton" type="button" onclick="hideComments();">'
+    . '<button class="btn btn-secondary" id="hidebutton" type="button" onclick="hideComments();">'
     . translate('Hide') . '</button><br>
   <div id="comtext">' . $comment_text . '</div>';
 // We could put the following JS in includes/js/view_entry.php,
diff --git a/views_edit.php b/views_edit.php
index fd0250918..b8bb07eb4 100644
--- a/views_edit.php
+++ b/views_edit.php
@@ -158,7 +158,7 @@
 </select>
 
 <?php if ( $GROUPS_ENABLED == 'Y' ) { ?>
-  <button class="btn" type="button" onclick="selectUsers()"><?php
+  <button class="btn btn-secondary" type="button" onclick="selectUsers()"><?php
     etranslate ( 'Select' );?>...</button>
 <?php } ?>
 </div>