diff --git a/analytics-ui/src/manage/extension-card.component.ts b/analytics-ui/src/manage/extension-card.component.ts
index fde428e..30b6bde 100644
--- a/analytics-ui/src/manage/extension-card.component.ts
+++ b/analytics-ui/src/manage/extension-card.component.ts
@@ -58,7 +58,7 @@ export class ExtensionCardComponent {
         // console.log("Confirmation delete result:", result);
         if (result) {
           try {
-            await this.analyticsService.deleteExtension(this.extension);
+            await this.analyticsService.deleteExtension(this.extension, true);
             this.extensionChanged.emit();
           } catch (ex) {
             if (ex) {
diff --git a/analytics-ui/src/manage/extension-grid.component.html b/analytics-ui/src/manage/extension-grid.component.html
index c604246..86f8adc 100644
--- a/analytics-ui/src/manage/extension-grid.component.html
+++ b/analytics-ui/src/manage/extension-grid.component.html
@@ -21,8 +21,12 @@
   <a
     href="https://cumulocity.com/guides/streaming-analytics/troubleshooting/#safe-mode-on-startup"
     target="'_blank'"
-    ><i c8yIcon="warning" class="animated fadeIn infinite" style="animation-duration: 1.5s"></i><span class="text-warning p-r-8 p-l-4">{{ 'Safe Mode' }}</span
-    ></a
+    ><i
+      c8yIcon="warning"
+      class="animated fadeIn infinite"
+      style="animation-duration: 1.5s"
+    ></i
+    ><span class="text-warning p-r-8 p-l-4">{{ 'Safe Mode' }}</span></a
   >
 </c8y-action-bar-item>
 
@@ -76,7 +80,7 @@
     class="btn btn-link"
     title="{{ 'Refresh' | translate }}"
   >
-    <i [ngClass]="{ 'icon-spin': loading }" c8yIcon="refresh"></i>
+    <i [ngClass]="{ 'icon-spin': (cepEngineStatus$ | async) === 'loading' }" c8yIcon="refresh"></i>
     {{ 'Refresh' | translate }}
   </button>
 </c8y-action-bar-item>
@@ -88,7 +92,7 @@
   ></c8y-list-display-switch>
 </c8y-action-bar-item>
 
-<div *ngIf="!loadingError && (extensions$ | async)?.length === 0" class="row">
+<div *ngIf="(cepEngineStatus$ | async) === 'empty'" class="row">
   <div class="col-lg-4 col-lg-offset-5 text-center">
     <c8y-ui-empty-state
       [icon]="'plugin'"
@@ -107,18 +111,10 @@
   </div>
 </div>
 
-<p class="text-center">
-  <c8y-progress-bar
-    message="Streaming Analytics Engine is restarting ..."
-    *ngIf="(cepOperationObject$ | async)?.c8y_Status?.status === 'Down'"
-  >
-  </c8y-progress-bar>
-</p>
-
 <div
   [ngClass]="listClass"
   class="card-group"
-  *ngIf="!loading && (cepOperationObject$ | async)?.c8y_Status?.status === 'Up'"
+  *ngIf="(cepEngineStatus$ | async) === 'up' || (cepEngineStatus$ | async) === 'loaded'"
 >
   <div
     class="page-sticky-header hidden-xs d-flex"
@@ -155,7 +151,7 @@
 <div
   class="col-lg-8 col-lg-offset-2 m-b-48 text-center"
   style="padding-top: 48px"
-  *ngIf="loadingError"
+  *ngIf="(cepEngineStatus$ | async) === 'loadingError'"
 >
   <h2>
     <span class="label label-primary text-14">
@@ -168,7 +164,7 @@ <h2>
 <div
   class="col-lg-8 col-lg-offset-2 m-b-48 text-center"
   style="padding-top: 48px"
-  *ngIf="loading"
+  *ngIf="(cepEngineStatus$ | async) === 'loading'"
 >
   <h2 class="p-b-24">
     <span class="label label-primary text-14">
@@ -177,3 +173,16 @@ <h2 class="p-b-24">
   </h2>
   <c8y-loading></c8y-loading>
 </div>
+
+<div
+  class="col-lg-8 col-lg-offset-2 m-b-48 text-center"
+  style="padding-top: 48px"
+  *ngIf="(cepEngineStatus$ | async) === 'down'"
+>
+  <h2 class="p-b-24">
+    <span class="label label-primary text-14">
+      Streaming Analytics Engine is restarting ...
+    </span>
+  </h2>
+  <c8y-loading></c8y-loading>
+</div>
diff --git a/analytics-ui/src/manage/extension-grid.component.ts b/analytics-ui/src/manage/extension-grid.component.ts
index 1f8837a..d3bb7d7 100644
--- a/analytics-ui/src/manage/extension-grid.component.ts
+++ b/analytics-ui/src/manage/extension-grid.component.ts
@@ -1,32 +1,40 @@
-import { Component, OnInit } from '@angular/core';
+import { Component, OnDestroy, OnInit } from '@angular/core';
 import { IManagedObject } from '@c8y/client';
-import { AlertService, WizardConfig, WizardModalService, gettext } from '@c8y/ngx-components';
+import {
+  AlertService,
+  WizardConfig,
+  WizardModalService,
+  gettext
+} from '@c8y/ngx-components';
 import { ModalOptions } from 'ngx-bootstrap/modal';
-import { BehaviorSubject, Observable, Subject, of } from 'rxjs';
-import { catchError, shareReplay, switchMap, tap } from 'rxjs/operators';
-import { AnalyticsService } from '../shared';
+import { BehaviorSubject, Observable, Subject, Subscription, of } from 'rxjs';
+import { catchError, shareReplay, switchMap, take, tap } from 'rxjs/operators';
+import { AnalyticsService, CEPEngineStatus, CEPStatusObject } from '../shared';
 
 @Component({
   selector: 'a17t-extension',
   templateUrl: './extension-grid.component.html',
   styleUrls: ['./extension-grid.component.css']
 })
-export class ExtensionGridComponent implements OnInit {
-  loading: boolean = false;
-  cepOperationObject$: Subject<any>;
-  cepCtrlStatus: any;
+export class ExtensionGridComponent implements OnInit, OnDestroy {
+  cepOperationObject$: Subject<IManagedObject>;
+  cepCtrlStatus: CEPStatusObject;
+  cepEngineStatus$: BehaviorSubject<CEPEngineStatus> =
+    new BehaviorSubject<CEPEngineStatus>('unknown');
   cepId: string;
-  loadingError: boolean = false;
   reload$: BehaviorSubject<boolean> = new BehaviorSubject(false);
   extensions$: Observable<IManagedObject[]>;
+  sub1: Subscription;
   listClass: string;
-  rescue: boolean = false;
 
   constructor(
     private analyticsService: AnalyticsService,
     private alertService: AlertService,
     private wizardModalService: WizardModalService
   ) {}
+  ngOnDestroy(): void {
+    this.sub1.unsubscribe();
+  }
 
   ngOnInit() {
     this.init();
@@ -38,21 +46,33 @@ export class ExtensionGridComponent implements OnInit {
     this.cepId = microservice_application_id as string;
     this.cepCtrlStatus = await this.analyticsService.getCEP_CtrlStatus();
     this.cepOperationObject$ = this.analyticsService.getCEP_OperationObject();
+    this.sub1 = this.cepOperationObject$.subscribe((mo) => {
+      if (mo.c8y_Status?.status === 'Down') {
+        this.cepEngineStatus$.next('down');
+      } else if (mo.c8y_Status?.status === 'Up') {
+        this.cepEngineStatus$.next('up');
+        // this.alertService.clearAll();
+      }
+    });
     this.extensions$ = this.reload$.pipe(
       tap((clearCache) => {
         if (clearCache) {
           this.analyticsService.clearCaches();
         }
-        this.loading = true;
-        this.loadingError = false;
+        this.cepEngineStatus$.next('loading');
       }),
       switchMap(() => this.analyticsService.getExtensionsMetadataEnriched()),
       catchError(() => {
-        this.loadingError = true;
-        this.loading = false;
+        this.cepEngineStatus$.next('loadingError');
         return of([]);
       }),
-      tap(() => (this.loading = false)),
+      tap((res) => {
+        if (res && res.length > 0) {
+          this.cepEngineStatus$.next('loaded');
+        } else {
+          this.cepEngineStatus$.next('empty');
+        }
+      }),
       shareReplay()
     );
 
@@ -78,14 +98,14 @@ export class ExtensionGridComponent implements OnInit {
       id: 'uploadAnalyticsExtension',
       componentInitialState: {
         mode: 'add',
-        headerText: 'Add extension',
-      },
+        headerText: 'Add extension'
+      }
     };
 
     const modalOptions: ModalOptions = { initialState };
 
     const modalRef = this.wizardModalService.show(modalOptions);
-    modalRef.content.onClose.subscribe(() => {
+    modalRef.content.onClose.pipe(take(1)).subscribe(() => {
       this.loadExtensions();
     });
   }
diff --git a/analytics-ui/src/shared/analytics.model.ts b/analytics-ui/src/shared/analytics.model.ts
index e948aeb..786759b 100644
--- a/analytics-ui/src/shared/analytics.model.ts
+++ b/analytics-ui/src/shared/analytics.model.ts
@@ -120,3 +120,10 @@ export const REPO_SAMPLES = [
     enabled: false
   }
 ] as Repository[];
+
+
+export type CEPEngineStatus = 'loading' | 'loaded' | 'empty' |'loadingError' | 'started' | 'down' | 'up' | 'unknown';
+
+export type CEPStatusObject = any;
+
+export type UploadMode = 'add' | 'update';
\ No newline at end of file
diff --git a/analytics-ui/src/shared/analytics.service.ts b/analytics-ui/src/shared/analytics.service.ts
index dd76680..639adda 100644
--- a/analytics-ui/src/shared/analytics.service.ts
+++ b/analytics-ui/src/shared/analytics.service.ts
@@ -27,7 +27,9 @@ import {
   EXTENSION_ENDPOINT,
   APPLICATION_ANALYTICS_BUILDER_SERVICE,
   CEP_METADATA_FILE_EXTENSION,
-  CEP_ENDPOINT
+  CEP_ENDPOINT,
+  CEPStatusObject,
+  UploadMode
 } from './analytics.model';
 import { isCustomCEP_Block, removeFileExtension } from './utils';
 
@@ -36,13 +38,12 @@ export class AnalyticsService {
   extensionChanged = new EventEmitter<IManagedObject>();
   progress: BehaviorSubject<number> = new BehaviorSubject<number>(null);
   private _cepOperationObjectId: Promise<string>;
-  private _cepCtrlStatus: Promise<any>;
+  private _cepCtrlStatus: Promise<CEPStatusObject>;
   private _blocksDeployed: Promise<CEP_Block[]>;
   private _extensionsDeployed: Promise<IManagedObject[]>;
   private _isBackendDeployed: Promise<boolean>;
-  private cepOperationObject$: BehaviorSubject<any> = new BehaviorSubject<any>(
-    {}
-  );
+  private cepOperationObject$: Subject<IManagedObject> =
+    new Subject<IManagedObject>();
   private realtime: Realtime;
 
   constructor(
@@ -117,9 +118,13 @@ export class AnalyticsService {
     return this._extensionsDeployed;
   }
 
-  async deleteExtension(app: IManagedObject): Promise<void> {
+  async deleteExtension(
+    app: IManagedObject,
+    showSuccessMessage
+  ): Promise<void> {
     await this.inventoryBinaryService.delete(app.id);
-    this.alertService.success(gettext('Extension deleted.'));
+    if (showSuccessMessage)
+      this.alertService.success(gettext('Extension deleted.'));
     this.extensionChanged.emit(app);
   }
 
@@ -251,11 +256,11 @@ export class AnalyticsService {
     return this._cepOperationObjectId;
   }
 
-  getCEP_OperationObject(): Subject<string> {
+  getCEP_OperationObject(): Subject<IManagedObject> {
     return this.cepOperationObject$;
   }
 
-  async getCEP_CtrlStatus(): Promise<any> {
+  async getCEP_CtrlStatus(): Promise<CEPStatusObject> {
     let response: IFetchResponse;
     if (!this._cepCtrlStatus) {
       if (await this.isBackendDeployed()) {
@@ -342,28 +347,31 @@ export class AnalyticsService {
     const url = '/service/cep/restart';
 
     try {
-        await this.fetchClient.fetch(url, fetchOptions);
+      await this.fetchClient.fetch(url, fetchOptions);
     } catch (e) {
-        console.error(e);
+      console.error(e);
     } finally {
-        console.log('We do cleanup here');
+      console.log('We do cleanup here');
     }
     this.clearCaches();
   }
 
   async uploadExtension(
-    archive: File,
-    newExtension: Partial<IManagedObject>,
-    // eslint-disable-next-line @typescript-eslint/no-unused-vars
-    restart: boolean = false,
-    mode : string,
-    extensionToReplace: IManagedObject
+    file: File,
+    extension: IManagedObject,
+    mode: UploadMode
   ): Promise<IManagedObjectBinary> {
+    let extensionToCreate: Partial<IManagedObject> = extension;
     if (mode === 'update') {
-        await this.deleteExtension(extensionToReplace);
+      await this.deleteExtension(extension, false);
+      extensionToCreate = {
+        name: extension.name,
+        pas_extension: extension.name
+      };
     }
-    const result2 = (await this.inventoryBinaryService.create(archive, newExtension))
-      .data;
+    const result2 = (
+      await this.inventoryBinaryService.create(file, extensionToCreate)
+    ).data;
     return result2;
   }
 
diff --git a/analytics-ui/src/shared/wizard/extension-add-wizard.component.ts b/analytics-ui/src/shared/wizard/extension-add-wizard.component.ts
index 2876820..38d5da0 100644
--- a/analytics-ui/src/shared/wizard/extension-add-wizard.component.ts
+++ b/analytics-ui/src/shared/wizard/extension-add-wizard.component.ts
@@ -2,6 +2,7 @@ import { Component, Input, OnInit } from '@angular/core';
 import { IManagedObject, IManagedObjectBinary } from '@c8y/client';
 import { gettext } from '@c8y/ngx-components';
 import { AnalyticsService } from '../analytics.service';
+import { UploadMode } from '../analytics.model';
 
 @Component({
   selector: 'a17t-extension-add-wizard',
@@ -10,11 +11,11 @@ import { AnalyticsService } from '../analytics.service';
     [headerIcon]="'upload'"
     [successText]="successText"
     [uploadExtensionHandler]="uploadExtensionHandler"
-    [canGoBack]="false"
+    [mode]="mode"
   ></a17t-extension-add>`
 })
 export class ExtensionAddWizardComponent implements OnInit {
-  @Input() mode: string;
+  @Input() mode: UploadMode;
   @Input() extensionToReplace: IManagedObject;
   @Input() headerText: string;
   successText: string = gettext('Extension created');
@@ -26,15 +27,21 @@ export class ExtensionAddWizardComponent implements OnInit {
 
   uploadExtensionHandler = (
     file: File,
-    newExtension: IManagedObject,
-    restart: boolean
-  ) => this.uploadExtension(file, newExtension, restart);
+    extension: IManagedObject,
+    mode: UploadMode
+  ) => this.uploadExtension(file, extension, mode);
 
   async uploadExtension(
     file: File,
-    newExtension: IManagedObject,
-    restart: boolean
+    extension: IManagedObject,
+    mode: UploadMode
   ): Promise<IManagedObjectBinary> {
-    return this.analyticsService.uploadExtension(file, newExtension, restart, this.mode, this.extensionToReplace);
+    // eslint-disable-next-line no-param-reassign
+    if(!extension) extension = this.extensionToReplace;
+    return this.analyticsService.uploadExtension(
+      file,
+      extension,
+      mode
+    );
   }
 }
diff --git a/analytics-ui/src/shared/wizard/extension-add.component.html b/analytics-ui/src/shared/wizard/extension-add.component.html
index c2e5478..2f36f2e 100644
--- a/analytics-ui/src/shared/wizard/extension-add.component.html
+++ b/analytics-ui/src/shared/wizard/extension-add.component.html
@@ -4,12 +4,12 @@ <h4>{{ headerText | translate }}</h4>
 </c8y-wizard-header>
 
 <div class="modal-inner-scroll animated fadeIn">
-  <div class="modal-body">
+  <div class="modal-body" style="min-height: 250px">
     <c8y-form-group
       *ngIf="!isAppCreated; else appCreated"
       [hasError]="errorMessage"
       class="m-auto"
-      style="max-width: 285px"
+      style="max-width: 400px"
     >
       <c8y-drop-area
         (dropped)="onFileDroppedEvent($event)"
@@ -18,15 +18,28 @@ <h4>{{ headerText | translate }}</h4>
         [maxAllowedFiles]="1"
         [message]="'Upload a *.zip file' | translate"
         [progress]="progress | async"
-        class="drop-area"
+        class="drop-area-sm"
       >
       </c8y-drop-area>
-      <c8y-messages>
-        <c8y-message *ngIf="errorMessage">
+      <c8y-messages class="m-t-8 m-b-8">
+        <c8y-message>
           {{ errorMessage | translate }}
         </c8y-message>
       </c8y-messages>
     </c8y-form-group>
+    <c8y-form-group
+      *ngIf="showUpdateDialog$ | async"
+      class="m-auto"
+    >
+      <button
+        class="btn btn-default btn-sm"
+        title="{{ 'Update' | translate }}"
+        translate
+        (click)="uploadExtension('update')"
+      >
+        Update existing extension
+      </button>
+    </c8y-form-group>
     <ng-template #appCreated>
       <div class="d-flex a-i-center j-c-center" style="min-height: 285px">
         <c8y-operation-result
@@ -42,16 +55,6 @@ <h4>{{ headerText | translate }}</h4>
   </div>
 </div>
 <c8y-wizard-footer>
-  <button
-    (click)="back()"
-    *ngIf="!isAppCreated && canGoBack"
-    class="btn btn-default"
-    title="{{ 'Back' | translate }}"
-    translate
-    type="button"
-  >
-    Back
-  </button>
   <button
     (click)="cancel()"
     *ngIf="!isAppCreated"
diff --git a/analytics-ui/src/shared/wizard/extension-add.component.ts b/analytics-ui/src/shared/wizard/extension-add.component.ts
index 549c899..0a5c8bc 100644
--- a/analytics-ui/src/shared/wizard/extension-add.component.ts
+++ b/analytics-ui/src/shared/wizard/extension-add.component.ts
@@ -1,5 +1,9 @@
 import { Component, Input, ViewChild } from '@angular/core';
-import { ApplicationService, IApplication, IManagedObject } from '@c8y/client';
+import {
+  ApplicationService,
+  IManagedObject,
+  IResultList
+} from '@c8y/client';
 import {
   AlertService,
   DropAreaComponent,
@@ -8,6 +12,7 @@ import {
 import { BehaviorSubject } from 'rxjs';
 import { ERROR_MESSAGES } from '../analytics.constants';
 import { AnalyticsService } from '../analytics.service';
+import { UploadMode } from '../analytics.model';
 
 @Component({
   selector: 'a17t-extension-add',
@@ -18,16 +23,19 @@ export class ExtensionAddComponent {
   @Input() headerIcon: string;
   @Input() successText: string;
   @Input() uploadExtensionHandler: any;
-  @Input() canGoBack: boolean = false;
+  @Input() mode: UploadMode;
 
   @ViewChild(DropAreaComponent) dropAreaComponent;
 
   isLoading: boolean;
   isAppCreated: boolean;
+  showUpdateDialog$: BehaviorSubject<boolean> = new BehaviorSubject<boolean>(
+    false
+  );
   createdApp: Partial<IManagedObject>;
   canOpenInBrowser: boolean = false;
   errorMessage: string;
-  restart: boolean = false;
+  fileToUpload: File;
   private uploadCanceled: boolean = false;
 
   constructor(
@@ -49,6 +57,7 @@ export class ExtensionAddComponent {
   }
 
   async onFile(file: File) {
+    this.fileToUpload = file;
     this.isLoading = true;
     this.errorMessage = null;
     this.progress.next(0);
@@ -58,9 +67,21 @@ export class ExtensionAddComponent {
         pas_extension: n,
         name: n
       };
-      await this.uploadExtensionHandler(file, this.createdApp, this.restart);
-      this.alertService.success('Uploaded new extension.');
-      this.isAppCreated = true;
+      const result: IResultList<IManagedObject> =
+        await this.analyticsService.getExtensionsMetadataFromInventory();
+      const { data } = result;
+      for (let i = 0; i < data.length; i++) {
+        const ext = data[i];
+        if (ext.name == n) {
+          if (this.mode == 'add') this.errorMessage = `Extension with the same name ${ext.name} exists!`;
+          this.showUpdateDialog$.next(true);
+          this.createdApp = ext;
+          break;
+        }
+      }
+      if (!this.errorMessage) {
+        await this.uploadExtension(this.mode);
+      }
     } catch (ex) {
       this.analyticsService.cancelExtensionCreation(this.createdApp);
       this.createdApp = null;
@@ -74,8 +95,17 @@ export class ExtensionAddComponent {
     this.isLoading = false;
   }
 
-  getHref(app: IApplication): string {
-    return this.applicationService.getHref(app);
+  private async uploadExtension(mode: UploadMode) {
+    await this.uploadExtensionHandler(
+      this.fileToUpload,
+      this.createdApp,
+      mode
+    );
+    this.alertService.success('Uploaded new extension.');
+    this.isAppCreated = true;
+    this.progress.next(100);
+    this.isLoading = false;
+    this.showUpdateDialog$.next(false);
   }
 
   cancel() {
@@ -87,10 +117,6 @@ export class ExtensionAddComponent {
     this.wizardComponent.close();
   }
 
-  back() {
-    this.wizardComponent.reset();
-  }
-
   private cancelFileUpload() {
     this.uploadCanceled = true;
     this.analyticsService.cancelExtensionCreation(this.createdApp);