How to Enable Application Verifier in Windbg

This is how you enable Application Verifier (appverif) if you are already in the debugger:

0:000> !gflag +vrf
Current NtGlobalFlag contents: 0x00000100
    vrf - Enable application verifier

You can then control verifier with the !avrf command.

This will display the current settings: 

0:000> !avrf Verifier package version >= 3.00 Application verifier settings (81000000): - no heap checking enabled! - SRWLock

Other notes:

If you see something like this, then verifier is not setup on the exe.

No type information found for `verifier!_DPH_HEAP_ROOT'.

Please fix the symbols for `verifier.dll'.