No provider for Router?

Please use this module

RouterModule.forRoot(
  [
    { path: "", component: LoginComponent}
  ]
)

now just replace your <login></login> with <router-outlet></router-outlet> thats it

I have also received this error when developing automatic tests for components. In this context the following import should be done:

import { RouterTestingModule } from "@angular/router/testing";

const testBedConfiguration = {
  imports: [SharedModule,
    BrowserAnimationsModule,
    RouterTestingModule.withRoutes([]),
  ],