disable/enable compilation errors in Netbeans

I've made the terrible mistake of telling Netbeans always to ignore compilation errors when running my Maven application.

Now that I want to revoke this, I can't seem to find an option anyway in the various configuration panels.

Does somebody know where this option can be changed ?

TIA !

Jan

For NetBeans 8.0.2 (in my case):

C:\Users\username\AppData\Roaming\NetBeans\8.0.2\config\Preferences\org\netbeans\modules\java\source\BuildArtifactMapperImpl.properties

file contains: askBeforeRunWithErrors=false

Set to true or file can be deleted, to reset.

Don't bother - found it after making a directory diff :

Stop Netbeans, remove the file underneath and start Netbeans again.

.netbeans/7.0/config/Preferences/org/netbeans/modules/java/source/BuildArtifactMapperImpl.properties

Simple, no ? :-)