title: Cannot read property 'outlets' of null
body: <p>I have next problem : <code>Cannot read property 'outlets' of null</code>. My project works, but after some time it stopped working, but i didn't change my code. Help me please.<br>
  <strong>Update</strong><br>
  My component with router-outlet:  </p>
  
  <pre class="lang-ts prettyprint-override"><code>import { Component } from '@angular/core';
  
  @Component({
    selector: 'app',
    template: '
      &lt;nav-menu&gt;&lt;/nav-menu&gt;
      &lt;router-outlet&gt;&lt;/router-outlet&gt;
      &lt;footer-component&gt;&lt;/footer-component&gt;
  
  ',
  })
  export class AppComponent  {}
  </code></pre>
  
  <p>app.module:  </p>
  
  <pre class="lang-ts prettyprint-override"><code>import { NgModule } from '@angular/core';
  import { BrowserModule } from '@angular/platform-browser';
  import { RouterModule } from '@angular/router';
  import { LocationStrategy, PathLocationStrategy, APP_BASE_HREF } from       '@angular/common';
  import { HttpModule } from '@angular/http';
  import {FormsModule,ReactiveFormsModule} from '@angular/forms';
  //+components
  @NgModule({
      imports:
      [
          BrowserModule,
          HttpModule,
          FormsModule,
          ReactiveFormsModule,
          RouterModule.forRoot([
              { path: '', component: HomeComponent },
              { path: 'home', component: HomeComponent },
              { path: 'blog', component: BlogComponent },
              { path: '2016/:link', component: BlogArticleFullComponent },
              {
                  path: 'admin', component: AdminComponent, 
                  children: [
                      { path: 'new', component: NewArticleComponent },
                      { path: 'new-writer', component: NewWriterComponent },
                      { path: 'new-tag', component: NewTagComponent }
                  ] },
              { path: '**', redirectTo: '', pathMatch: 'full'}
          ])
      ],
      declarations:
      [//components
      ],
      bootstrap:
      [
          AppComponent
      ],
      providers:
      [
          { provide: APP_BASE_HREF, useValue: '/' },
          { provide: LocationStrategy, useClass: PathLocationStrategy }
      ]
  })
  export class AppModule { }
  </code></pre>
  
  <p>P.S. There is ' quote against ` because stackoverflow ``-is code.</p>