I blogged previously about the following error message:
Cannot find module '@angular-devkit/core'
I got some feedback that the second solution I shared(updating the Angular CLI version) didn’t work for everyone. Turns out that you also need to update the local version of the Angular-CLI:
npm install --save-dev @angular/cli@latest
npm install
More information about updating the Angular CLI can be found in the documentation: https://github.com/angular/angular-cli