diff --git a/src/Squidex.Domain.Apps.Entities/Apps/AppHistoryEventsCreator.cs b/src/Squidex.Domain.Apps.Entities/Apps/AppHistoryEventsCreator.cs
index d36f551f0..e8aee083d 100644
--- a/src/Squidex.Domain.Apps.Entities/Apps/AppHistoryEventsCreator.cs
+++ b/src/Squidex.Domain.Apps.Entities/Apps/AppHistoryEventsCreator.cs
@@ -53,7 +53,7 @@ namespace Squidex.Domain.Apps.Entities.Apps
                 "added pattern {[Name]}");
 
             AddEventMessage<AppPatternDeleted>(
-                "deleted pattern {[Name]}");
+                "deleted pattern {[PatternId]}");
 
             AddEventMessage<AppPatternUpdated>(
                 "updated pattern {[Name]}");
@@ -164,7 +164,7 @@ namespace Squidex.Domain.Apps.Entities.Apps
 
             return Task.FromResult(
                 ForEvent(@event, channel)
-                    .AddParameter("Name", @event.Name));
+                    .AddParameter("PatternId", @event.PatternId));
         }
 
         protected override Task<HistoryEventToStore> CreateEventCoreAsync(Envelope<IEvent> @event)
diff --git a/src/Squidex.Domain.Apps.Events/Apps/AppPatternDeleted.cs b/src/Squidex.Domain.Apps.Events/Apps/AppPatternDeleted.cs
index 0759e3fb3..3ae54ab42 100644
--- a/src/Squidex.Domain.Apps.Events/Apps/AppPatternDeleted.cs
+++ b/src/Squidex.Domain.Apps.Events/Apps/AppPatternDeleted.cs
@@ -14,7 +14,5 @@ namespace Squidex.Domain.Apps.Events.Apps
     public sealed class AppPatternDeleted : AppEvent
     {
         public Guid PatternId { get; set; }
-
-        public string Name { get; set; }
     }
 }
diff --git a/src/Squidex/app/features/administration/pages/event-consumers/event-consumers-page.component.html b/src/Squidex/app/features/administration/pages/event-consumers/event-consumers-page.component.html
index 14c598818..540d8fde1 100644
--- a/src/Squidex/app/features/administration/pages/event-consumers/event-consumers-page.component.html
+++ b/src/Squidex/app/features/administration/pages/event-consumers/event-consumers-page.component.html
@@ -60,11 +60,11 @@
 </sqx-panel>
 
 <sqx-modal-dialog *sqxModalView="eventConsumerErrorDialog;onRoot:true" (closed)="eventConsumerErrorDialog.hide()">
-    <ng-container #title>
+    <ng-container title>
         Error
     </ng-container>
 
-    <ng-container #content>
+    <ng-container content>
         <textarea readonly class="form-control error-message">{{eventConsumerError}}</textarea>
     </ng-container>
 </sqx-modal-dialog>
\ No newline at end of file
diff --git a/src/Squidex/app/framework/angular/http/http-extensions.ts b/src/Squidex/app/framework/angular/http/http-extensions.ts
index b215d1ce9..fd5b7e29a 100644
--- a/src/Squidex/app/framework/angular/http/http-extensions.ts
+++ b/src/Squidex/app/framework/angular/http/http-extensions.ts
@@ -67,7 +67,11 @@ export const pretifyError = (message: string) => <T>(source: Observable<T>) =>
 
         if (!Types.is(response.error, Error)) {
             try {
-                const errorDto = Types.isObject(response.error) ? response.error : JSON.parse(response.error);
+                let errorDto = Types.isObject(response.error) ? response.error : JSON.parse(response.error);
+
+                if (!errorDto) {
+                    errorDto = { message: 'Failed to make the request.', details: [] };
+                }
 
                 if (response.status === 412) {
                     result = new ErrorDto(response.status, 'Failed to make the update. Another user has made a change. Please reload.');
diff --git a/src/Squidex/app/shared/state/contributors.state.ts b/src/Squidex/app/shared/state/contributors.state.ts
index 2b218bcd8..4b1ed31f4 100644
--- a/src/Squidex/app/shared/state/contributors.state.ts
+++ b/src/Squidex/app/shared/state/contributors.state.ts
@@ -6,14 +6,16 @@
  */
 
 import { Injectable } from '@angular/core';
-import { Observable } from 'rxjs';
-import { distinctUntilChanged, map, tap } from 'rxjs/operators';
+import { Observable, throwError } from 'rxjs';
+import { catchError, distinctUntilChanged, map, tap } from 'rxjs/operators';
 
 import {
     DialogService,
+    ErrorDto,
     ImmutableArray,
     notify,
     State,
+    Types,
     Version
 } from '@app/framework';
 
@@ -100,6 +102,13 @@ export class ContributorsState extends State<Snapshot> {
 
                 this.replaceContributors(contributors, dto.version);
             }),
+            catchError(error => {
+                if (Types.is(error, ErrorDto) && error.statusCode === 404) {
+                    return throwError(new ErrorDto(404, 'The user does not exist.'));
+                } else {
+                    return throwError(error);
+                }
+            }),
             notify(this.dialogs));
     }
 
diff --git a/src/Squidex/package.json b/src/Squidex/package.json
index 55c6b4665..5ab170f23 100644
--- a/src/Squidex/package.json
+++ b/src/Squidex/package.json
@@ -34,6 +34,7 @@
     "moment": "2.22.2",
     "mousetrap": "1.6.2",
     "ng2-dnd": "5.0.2",
+    "npm": "^6.2.0",
     "oidc-client": "1.4.1",
     "pikaday": "1.7.0",
     "progressbar.js": "1.0.1",