title: Angular2 - 'router-outlet' is not a known element
body: <p>I created routes with deep child paths. I added <code>&lt;router-outlet&gt;</code> to the <em>AdminComponent</em> component which I wrapped into NgModule. But after refreshing the page I got this error:</p>
  
  <pre><code>'router-outlet' is not a known element
  </code></pre>
  
  <p>Maybe it occurred because I forgot import some module to <em>admin.module.ts</em></p>
  
  <p>Please help. Thanks.</p>
  
  <p><em>app.routes.ts</em></p>
  
  <pre class="lang-js prettyprint-override"><code>export const routes: Routes = [
      {
          path: '',
          component: AppComponent,
          children: [
              {
                  path: '',
                  component: LoginComponent
              },
              {
                  path: 'admin',
                  component: AdminComponent
              },
              {
                  path: 'user',
                  component: UserComponent
              },
              {
                  path: 'there',
                  component: ThereComponent
              }
          ]
      }
  ]
  </code></pre>
  
  
  
  <p><em>app.module.ts</em></p>
  
  <pre class="lang-js prettyprint-override"><code>@NgModule({
      imports: [
          BrowserModule,
          AppRoutes,
          FormsModule,
          ReactiveFormsModule,
          HttpModule,
          RouterModule,
          TranslateModule.forRoot({
              provide: TranslateLoader,
              useFactory: (http: Http) =&gt; {
                  return new TranslateStaticLoader(http, './src/assets/i18n', '.json')
              },
              deps: [Http]
          }),
          UserComponentModule,
          AdminComponentModule,
          LoginComponentModule,
          ThereComponentModule,
          DashboardComponentModule
      ],
      declarations: [
          AppComponent
      ],
      providers: [
          FormBuilder
      ],
      bootstrap: [AppComponent]
  })
  </code></pre>
  
  
  
  <p><em>admin.component.ts</em> and <em>admin.module.ts</em></p>
  
  <pre class="lang-js prettyprint-override"><code>//  admin.component.ts
  import {Component} from "@angular/core";
  
  @Component({
      selector: 'admin',
      template: "&lt;router-outlet&gt;&lt;/router-outlet&gt;",
  })
  
  export class AdminComponent {
      constructor() {
  
      }
  }
  
  //  admin.module.ts
  const ADMIN_DECLARATION = [
      AdminComponent
  ];
  
  @NgModule({
      imports: [
          BrowserModule,
          TranslateModule,
          FormsModule,
          ReactiveFormsModule
      ],
      declarations: [
          ADMIN_DECLARATION
      ],
      exports: [
          ADMIN_DECLARATION
      ],
      providers: [
          TranslateService,
          FormBuilder
      ]
  })
  
  export class AdminComponentModule {
  
  }
  </code></pre>