Angular 9 - NGCC fails with an unhandled exception

Question

Buidling the application after having upgraded dependcies to Angular 9 (and having performed necessary code changes) throws an error:

Compiling @ang

Answer 1

Using terminal/cmd,

1st Step: ng update @angular/cli @angular/core

2nd Step: ng update

3rd Step: ng serve

Fixed mine.

NOTE Your custom css files in bootstrap folder might get deleted. Back them up before and place them back after the update!