This error means that an NgModule that was used for bootstrapping an application is missing key information for Angular to proceed with the bootstrap process.
The error happens when the NgModule bootstrap property is missing (or is an empty array) in the @NgModule annotation and there is no ngDoBootstrap lifecycle hook defined on that NgModule class.
More information about the bootstrapping process can be found in this guide.
The following examples will trigger the error.
@NgModule({ declarations: [AppComponent], imports: [BrowserModule, AppRoutingModule], providers: [],})export class AppModule {}// The `AppModule` is used for bootstrapping, but the `@NgModule.bootstrap` field is missing.platformBrowser().bootstrapModule(AppModule);
@NgModule({ declarations: [AppComponent], imports: [BrowserModule, AppRoutingModule], providers: [], bootstrap: [],})export class AppModule {}// The `AppModule` is used for bootstrapping, but the `@NgModule.bootstrap` field contains an empty array.platformBrowser().bootstrapModule(AppModule);
Debugging the error
Please make sure that the NgModule that is used for bootstrapping is setup correctly:
- either the
bootstrapproperty exists (and contains a non-empty array) in the@NgModuleannotation - or the
ngDoBootstrapmethod exists on the NgModule class