diff --git a/src/platform.h b/src/platform.h
index 8ad5cee..767166f 100644
--- a/src/platform.h
+++ b/src/platform.h
@@ -94,6 +94,13 @@ struct platform {
 	* is called.
 	*/
 	void (*commit)();
+
+	/*
+	 * Display an error modal dialog to the user.
+	 * This function should block until the user dismisses the dialog
+	 * or a timeout occurs (recommended: 10 seconds).
+	 */
+	void (*show_error_modal)(const char *title, const char *message);
 };
 
 void platform_run(int (*main) (struct platform *platform));
diff --git a/src/platform/linux/X/X.c b/src/platform/linux/X/X.c
index d1c0dd3..0a89fea 100644
--- a/src/platform/linux/X/X.c
+++ b/src/platform/linux/X/X.c
@@ -201,7 +201,9 @@ void x_init(struct platform *platform)
 {
 	dpy = XOpenDisplay(NULL);
 	if (!dpy) {
-		fprintf(stderr, "Could not connect to X server\n");
+		/* Since we can't show a modal without X11, just use fprintf */
+		fprintf(stderr, "ERROR: Could not connect to X server\n");
+		fprintf(stderr, "Please make sure X11 is running and DISPLAY is set correctly.\n");
 		exit(-1);
 	}
 
@@ -231,4 +233,104 @@ void x_init(struct platform *platform)
 	platform->screen_get_dimensions = x_screen_get_dimensions;
 	platform->screen_list = x_screen_list;
 	platform->scroll = x_scroll;
+	platform->show_error_modal = x_show_error_modal;
+}
+
+void x_show_error_modal(const char *title, const char *message)
+{
+	if (!dpy)
+		return;
+
+	Window root = DefaultRootWindow(dpy);
+	int screen = DefaultScreen(dpy);
+	
+	/* Create a simple modal window */
+	int win_w = 400;
+	int win_h = 150;
+	int scr_w = DisplayWidth(dpy, screen);
+	int scr_h = DisplayHeight(dpy, screen);
+	int x = (scr_w - win_w) / 2;
+	int y = (scr_h - win_h) / 2;
+	
+	Window win = XCreateSimpleWindow(dpy, root, x, y, win_w, win_h, 2,
+					 BlackPixel(dpy, screen),
+					 WhitePixel(dpy, screen));
+	
+	/* Set window properties */
+	XStoreName(dpy, win, title);
+	XSelectInput(dpy, win, ExposureMask | KeyPressMask | ButtonPressMask);
+	
+	/* Set window type to dialog */
+	Atom wm_type = XInternAtom(dpy, "_NET_WM_WINDOW_TYPE", False);
+	Atom wm_type_dialog = XInternAtom(dpy, "_NET_WM_WINDOW_TYPE_DIALOG", False);
+	XChangeProperty(dpy, win, wm_type, XA_ATOM, 32, PropModeReplace,
+			(unsigned char *)&wm_type_dialog, 1);
+	
+	/* Set it to be on top */
+	Atom wm_state = XInternAtom(dpy, "_NET_WM_STATE", False);
+	Atom wm_state_above = XInternAtom(dpy, "_NET_WM_STATE_ABOVE", False);
+	XChangeProperty(dpy, win, wm_state, XA_ATOM, 32, PropModeReplace,
+			(unsigned char *)&wm_state_above, 1);
+	
+	XMapWindow(dpy, win);
+	XRaiseWindow(dpy, win);
+	XFlush(dpy);
+	
+	/* Draw the message */
+	GC gc = XCreateGC(dpy, win, 0, NULL);
+	XSetForeground(dpy, gc, BlackPixel(dpy, screen));
+	
+	/* Simple text rendering - split message into lines */
+	int text_y = 30;
+	const char *line_start = message;
+	char line_buf[256];
+	
+	while (*line_start) {
+		const char *line_end = strchr(line_start, '\n');
+		int line_len;
+		
+		if (line_end) {
+			line_len = line_end - line_start;
+			if (line_len > 255) line_len = 255;
+			strncpy(line_buf, line_start, line_len);
+			line_buf[line_len] = '\0';
+			line_start = line_end + 1;
+		} else {
+			strncpy(line_buf, line_start, 255);
+			line_buf[255] = '\0';
+			line_start += strlen(line_start);
+		}
+		
+		XDrawString(dpy, win, gc, 10, text_y, line_buf, strlen(line_buf));
+		text_y += 20;
+		
+		if (!*line_start)
+			break;
+	}
+	
+	XDrawString(dpy, win, gc, 10, win_h - 20, "Press any key or click to dismiss", 34);
+	XFlush(dpy);
+	
+	/* Wait for user input with 10 second timeout */
+	struct timeval tv;
+	fd_set fds;
+	int x11_fd = ConnectionNumber(dpy);
+	
+	tv.tv_sec = 10;
+	tv.tv_usec = 0;
+	
+	FD_ZERO(&fds);
+	FD_SET(x11_fd, &fds);
+	
+	int ret = select(x11_fd + 1, &fds, NULL, NULL, &tv);
+	
+	if (ret > 0) {
+		/* Wait for any event */
+		XEvent ev;
+		XNextEvent(dpy, &ev);
+	}
+	
+	XFreeGC(dpy, gc);
+	XDestroyWindow(dpy, win);
+	XFlush(dpy);
 }
diff --git a/src/platform/linux/X/X.h b/src/platform/linux/X/X.h
index 83202cd..8202106 100644
--- a/src/platform/linux/X/X.h
+++ b/src/platform/linux/X/X.h
@@ -105,6 +105,7 @@ void x_copy_selection();
 void x_commit();
 void x_monitor_file(const char *path);
 long x_get_mtime(const char *path);
+void x_show_error_modal(const char *title, const char *message);
 
 extern struct monitored_file monitored_files[32];
 extern size_t nr_monitored_files;
diff --git a/src/platform/linux/X/input.c b/src/platform/linux/X/input.c
index 1f7c09c..533bee4 100644
--- a/src/platform/linux/X/input.c
+++ b/src/platform/linux/X/input.c
@@ -141,9 +141,15 @@ static uint8_t process_xinput_event(XEvent *ev, int *state, int *mods)
 static const char *xerr_key = NULL;
 static int input_xerr(Display *dpy, XErrorEvent *ev)
 {
-	fprintf(stderr,
-		"ERROR: Failed to grab %s (ensure it isn't mapped by another application)\n",
+	char error_msg[256];
+	snprintf(error_msg, sizeof(error_msg),
+		"Failed to grab key: %s\n\n"
+		"Make sure it isn't mapped by another application.",
 		xerr_key);
+	
+	/* Show error modal */
+	x_show_error_modal("Keyboard Grab Failed", error_msg);
+	
 	return 0;
 }
 
diff --git a/src/platform/linux/wayland/wayland.c b/src/platform/linux/wayland/wayland.c
index d479bb6..fca8c8c 100644
--- a/src/platform/linux/wayland/wayland.c
+++ b/src/platform/linux/wayland/wayland.c
@@ -235,4 +235,93 @@ void wayland_init(struct platform *platform)
 	platform->screen_get_dimensions = way_screen_get_dimensions;
 	platform->screen_list = way_screen_list;
 	platform->scroll = way_scroll;
+	platform->show_error_modal = way_show_error_modal;
+}
+
+void way_show_error_modal(const char *title, const char *message)
+{
+	/* For Wayland, we'll create a simple overlay window with the error message */
+	if (nr_screens == 0 || !wl.dpy)
+		return;
+
+	struct screen *scr = &screens[0];
+	int win_w = 400;
+	int win_h = 150;
+	int x = (scr->w - win_w) / 2;
+	int y = (scr->h - win_h) / 2;
+
+	/* Create a surface for the error modal */
+	struct surface *sfc = create_surface(scr, x, y, win_w, win_h, 1);
+	if (!sfc)
+		return;
+
+	/* Get cairo context from screen */
+	cairo_t *cr = scr->cr;
+	if (!cr)
+		return;
+
+	/* Draw white background */
+	cairo_set_source_rgb(cr, 1.0, 1.0, 1.0);
+	cairo_rectangle(cr, x, y, win_w, win_h);
+	cairo_fill(cr);
+
+	/* Draw border */
+	cairo_set_source_rgb(cr, 0.0, 0.0, 0.0);
+	cairo_set_line_width(cr, 2.0);
+	cairo_rectangle(cr, x, y, win_w, win_h);
+	cairo_stroke(cr);
+
+	/* Draw title */
+	cairo_set_source_rgb(cr, 0.0, 0.0, 0.0);
+	cairo_select_font_face(cr, "sans-serif", CAIRO_FONT_SLANT_NORMAL,
+			       CAIRO_FONT_WEIGHT_BOLD);
+	cairo_set_font_size(cr, 14.0);
+	cairo_move_to(cr, x + 10, y + 25);
+	cairo_show_text(cr, title);
+
+	/* Draw message */
+	cairo_select_font_face(cr, "sans-serif", CAIRO_FONT_SLANT_NORMAL,
+			       CAIRO_FONT_WEIGHT_NORMAL);
+	cairo_set_font_size(cr, 12.0);
+
+	int text_y = y + 50;
+	const char *line_start = message;
+	char line_buf[256];
+
+	while (*line_start) {
+		const char *line_end = strchr(line_start, '\n');
+		int line_len;
+
+		if (line_end) {
+			line_len = line_end - line_start;
+			if (line_len > 255) line_len = 255;
+			strncpy(line_buf, line_start, line_len);
+			line_buf[line_len] = '\0';
+			line_start = line_end + 1;
+		} else {
+			strncpy(line_buf, line_start, 255);
+			line_buf[255] = '\0';
+			line_start += strlen(line_start);
+		}
+
+		cairo_move_to(cr, x + 10, text_y);
+		cairo_show_text(cr, line_buf);
+		text_y += 20;
+
+		if (!*line_start)
+			break;
+	}
+
+	/* Draw dismiss hint */
+	cairo_move_to(cr, x + 10, y + win_h - 20);
+	cairo_show_text(cr, "Will auto-dismiss in 10 seconds...");
+
+	surface_show(sfc);
+	wl_display_flush(wl.dpy);
+
+	/* Wait for 10 seconds */
+	sleep(10);
+
+	destroy_surface(sfc);
+	wl_display_flush(wl.dpy);
 }
diff --git a/src/platform/linux/wayland/wayland.h b/src/platform/linux/wayland/wayland.h
index 022fc72..16a7575 100644
--- a/src/platform/linux/wayland/wayland.h
+++ b/src/platform/linux/wayland/wayland.h
@@ -126,5 +126,6 @@ void way_copy_selection();
 void way_commit();
 void way_init();
 void init_input();
+void way_show_error_modal(const char *title, const char *message);
 
 #endif
diff --git a/src/platform/macos/input.m b/src/platform/macos/input.m
index 9ec38ca..f17add1 100644
--- a/src/platform/macos/input.m
+++ b/src/platform/macos/input.m
@@ -499,9 +499,11 @@ void macos_init_input()
 
 
 	if (!tap) {
-		fprintf(stderr,
-			"Failed to create event tap, make sure warpd is "
-			"whitelisted as an accessibility feature.\n");
+		/* Show error modal before exiting */
+		osx_show_error_modal("Accessibility Permission Required",
+			"Failed to create event tap.\n\n"
+			"Please make sure warpd is whitelisted as an\n"
+			"accessibility feature in System Settings.");
 		exit(-1);
 	}
 
diff --git a/src/platform/macos/macos.h b/src/platform/macos/macos.h
index a42397f..ac55e68 100644
--- a/src/platform/macos/macos.h
+++ b/src/platform/macos/macos.h
@@ -124,5 +124,6 @@ void osx_copy_selection();
 void osx_monitor_file(const char *_path);
 void osx_input_interrupt();
 void osx_commit();
+void osx_show_error_modal(const char *title, const char *message);
 
 #endif
diff --git a/src/platform/macos/macos.m b/src/platform/macos/macos.m
index 962813e..e887c17 100644
--- a/src/platform/macos/macos.m
+++ b/src/platform/macos/macos.m
@@ -186,6 +186,7 @@ void osx_commit()
 		.screen_list = osx_screen_list,
 		.scroll = osx_scroll,
 		.monitor_file = osx_monitor_file,
+		.show_error_modal = osx_show_error_modal,
 	};
 
 	main(&platform);
@@ -208,3 +209,21 @@ void platform_run(int (*main)(struct platform *platform))
 
 	[NSApp run];
 }
+
+void osx_show_error_modal(const char *title, const char *message)
+{
+	dispatch_async(dispatch_get_main_queue(), ^{
+		NSAlert *alert = [[NSAlert alloc] init];
+		[alert setMessageText:[NSString stringWithUTF8String:title]];
+		[alert setInformativeText:[NSString stringWithUTF8String:message]];
+		[alert setAlertStyle:NSAlertStyleCritical];
+		[alert addButtonWithTitle:@"OK"];
+		
+		/* Run the alert modally with a timeout */
+		[alert runModal];
+	});
+	
+	/* Give the modal time to display */
+	sleep(1);
+}
+
diff --git a/src/platform/windows/windows.c b/src/platform/windows/windows.c
index 8bc98b6..8512f9a 100755
--- a/src/platform/windows/windows.c
+++ b/src/platform/windows/windows.c
@@ -472,6 +472,13 @@ void platform_run(int (*main)(struct platform *platform))
 	platform.input_lookup_code = input_lookup_code;
 	platform.input_lookup_name = input_lookup_name;
 	platform.monitor_file = wn_monitor_file;
+	platform.show_error_modal = wn_show_error_modal;
 
 	exit(main(&platform));
 }
+
+void wn_show_error_modal(const char *title, const char *message)
+{
+	/* Use Windows MessageBox API for error display */
+	MessageBoxA(NULL, message, title, MB_OK | MB_ICONERROR | MB_TOPMOST);
+}
diff --git a/src/platform/windows/windows.h b/src/platform/windows/windows.h
index 9ff4c5c..a3ce691 100755
--- a/src/platform/windows/windows.h
+++ b/src/platform/windows/windows.h
@@ -22,5 +22,6 @@ void wn_screen_get_dimensions(struct screen *scr, int *xoff, int *yoff, int *w,
 void wn_screen_set_hints(struct screen *scr, struct hint *hints, size_t nhints);
 void wn_screen_set_hintinfo(COLORREF _hint_bgcol, COLORREF _hint_fgcol);
 void wn_monitor_file(const char *path);
+void wn_show_error_modal(const char *title, const char *message);
 
 #endif
diff --git a/src/warpd.c b/src/warpd.c
index 3f14701..e39b9e5 100644
--- a/src/warpd.c
+++ b/src/warpd.c
@@ -18,6 +18,17 @@ uint64_t get_time_us()
 	return ts.tv_nsec / 1E3 + ts.tv_sec * 1E6;
 }
 
+void show_error_modal(const char *title, const char *message)
+{
+	/* Log to stderr as well for debugging/logging purposes */
+	fprintf(stderr, "ERROR: %s: %s\n", title, message);
+
+	/* Show modal if platform is initialized and supports it */
+	if (platform && platform->show_error_modal) {
+		platform->show_error_modal(title, message);
+	}
+}
+
 
 const char *get_data_path(const char *file)
 {
diff --git a/src/warpd.h b/src/warpd.h
index 258c8d4..3173224 100644
--- a/src/warpd.h
+++ b/src/warpd.h
@@ -148,5 +148,7 @@ extern struct config_entry *config;
 int mode_loop(int initial_mode, int oneshot, int record_history);
 void daemon_loop(const char *config_path);
 
+void show_error_modal(const char *title, const char *message);
+
 extern struct platform *platform;
 #endif