diff --git a/@overflow/commons/ui/component/menu/menu-bar.component.html b/@overflow/commons/ui/component/menu/menu-bar.component.html
index cc34d42..fe9e945 100644
--- a/@overflow/commons/ui/component/menu/menu-bar.component.html
+++ b/@overflow/commons/ui/component/menu/menu-bar.component.html
@@ -13,20 +13,6 @@
       </button>
     </div>
   </div>
-  <div class="toolbar-dropdown closed" role="menuitem" aria-expanded="false">
-    <div class="toolbar-button">
-      <button class="button-component" type="button" tabindex="-1">
-        <div class="menu-item">
-          <div class="label">
-            <span aria-label="Edit">
-              <span aria-hidden="true" class="access-key">E</span>
-              <span aria-hidden="true">dit</span>
-            </span>
-          </div>
-        </div>
-      </button>
-    </div>
-  </div>
   <div class="toolbar-dropdown closed" role="menuitem" aria-expanded="false">
     <div class="toolbar-button">
       <button class="button-component" type="button" tabindex="-1">
@@ -46,23 +32,9 @@
       <button class="button-component" type="button" tabindex="-1">
         <div class="menu-item">
           <div class="label">
-            <span aria-label="Repository">
-              <span aria-hidden="true" class="access-key">R</span>
-              <span aria-hidden="true">epository</span>
-            </span>
-          </div>
-        </div>
-      </button>
-    </div>
-  </div>
-  <div class="toolbar-dropdown closed" role="menuitem" aria-expanded="false">
-    <div class="toolbar-button">
-      <button class="button-component" type="button" tabindex="-1">
-        <div class="menu-item">
-          <div class="label">
-            <span aria-label="Branch">
-              <span aria-hidden="true" class="access-key">B</span>
-              <span aria-hidden="true">ranch</span>
+            <span aria-label="Setting">
+              <span aria-hidden="true" class="access-key">S</span>
+              <span aria-hidden="true">etting</span>
             </span>
           </div>
         </div>
diff --git a/@overflow/commons/ui/component/menu/menu-bar.component.ts b/@overflow/commons/ui/component/menu/menu-bar.component.ts
index 4b51a6d..e01760b 100644
--- a/@overflow/commons/ui/component/menu/menu-bar.component.ts
+++ b/@overflow/commons/ui/component/menu/menu-bar.component.ts
@@ -13,82 +13,6 @@ export class MenuBarComponent implements OnInit {
   ) { }
 
   ngOnInit() {
-    this.items = [
-      {
-        label: 'File',
-        icon: 'pi pi-fw pi-file',
-        items: [{
-          label: 'New',
-          icon: 'pi pi-fw pi-plus',
-          items: [
-            { label: 'Project' },
-            { label: 'Other' },
-          ]
-        },
-        { label: 'Open' },
-        { separator: true },
-        { label: 'Quit' }
-        ]
-      },
-      {
-        label: 'Edit',
-        icon: 'pi pi-fw pi-pencil',
-        items: [
-          { label: 'Delete', icon: 'pi pi-fw pi-trash' },
-          { label: 'Refresh', icon: 'pi pi-fw pi-refresh' }
-        ]
-      },
-      {
-        label: 'Help',
-        icon: 'pi pi-fw pi-question',
-        items: [
-          {
-            label: 'Contents'
-          },
-          {
-            label: 'Search',
-            icon: 'pi pi-fw pi-search',
-            items: [
-              {
-                label: 'Text',
-                items: [
-                  {
-                    label: 'Workspace'
-                  }
-                ]
-              },
-              {
-                label: 'File'
-              }
-            ]
-          }
-        ]
-      },
-      {
-        label: 'Actions',
-        icon: 'pi pi-fw pi-cog',
-        items: [
-          {
-            label: 'Edit',
-            icon: 'pi pi-fw pi-pencil',
-            items: [
-              { label: 'Save', icon: 'pi pi-fw pi-save' },
-              { label: 'Update', icon: 'pi pi-fw pi-save' },
-            ]
-          },
-          {
-            label: 'Other',
-            icon: 'pi pi-fw pi-tags',
-            items: [
-              { label: 'Delete', icon: 'pi pi-fw pi-minus' }
-            ]
-          }
-        ]
-      },
-      {
-        label: 'Quit', icon: 'pi pi-fw pi-times'
-      }
-    ];
   }
 
   onTitlebarDoubleClick() {
diff --git a/src/app/pages/home/home-page.component.ts b/src/app/pages/home/home-page.component.ts
index 7d99feb..2fae314 100644
--- a/src/app/pages/home/home-page.component.ts
+++ b/src/app/pages/home/home-page.component.ts
@@ -273,7 +273,7 @@ export class HomePageComponent implements OnInit, OnDestroy {
   @RPCSubscriber({ method: 'DiscoveryService.DiscoveryStop' })
   public DiscoveryStop(stopDate: Date) {
     console.log('DiscoveryStop', stopDate);
-
+    this.discoveryConfigService.setStarted(false);
     this.simulation.stop();
   }
 
diff --git a/src/app/pages/pages.component.html b/src/app/pages/pages.component.html
index de1ee53..d5097a9 100644
--- a/src/app/pages/pages.component.html
+++ b/src/app/pages/pages.component.html
@@ -1,7 +1,7 @@
 <app-toolbar>
   <app-nic-dropdown [blockTarget]="pagesContent" (select)="onNICSelect($event)"></app-nic-dropdown>
   <app-scanner-setting-dropdown [blockTarget]="pagesContent" (ready)="onConfigReady($event)"></app-scanner-setting-dropdown>
-  <div class="toolbar-button push-pull-button" style="width: 32px">
+  <div class="toolbar-button push-pull-button" style="width: 32px" [hidden]="discoveryConfigService.started | async">
     <button class="button-component" type="button" (click)="onStart()">
       <svg aria-hidden="true" class="octicon icon" version="1.1" viewBox="0 0 15 17">
         <path d="M0.2,15.6c0,0.2,0.1,0.4,0.2,0.6c0.4,0.6,1.2,0.8,1.8,0.5l12.2-7.1c0.2-0.1,0.3-0.3,0.4-0.4