PS C:\ionic\appmysql> ionic serve
> ng.cmd run app:serve --host=localhost --port=8100
[ng] An unhandled exception occurred: ngcc is already running at process with id 12260.
[ng] If you are running multiple builds in parallel then you might try pre-processing your node_modules via the command line ngcc tool before starting the builds.
cli/ngcc/__ngcc_lock_file__.)
[ng] See "C:\Users\AlvgMaker\AppData\Local\Temp\ng-Imd7P3\angular-errors.log" for further details.
[ERROR] ng has unexpectedly closed (exit code 127).