Cannot read property 'outlets' of null

For future reference: I got this error when using [routerLink] with an array which looked like ['/foo', null]. Fixed it by supplying an object instead of null.

Most times this has nothing to do with your route configuration but happens when you try to pass in a dynamic data as a parameter to the route for instance.

<a [routerLink]="['/user', user?.id]" />user profile</a>

The user.id is dynamic and at the point where the page is initialized, the user object might be null hence the error.

A quick fix to this will be to add an ng-if to the link, this will force the link to initialize only when the user object is available.

<a [routerLink]="['/user', user?.id]" *ngIf="user" />user profile</a>