This is problem is probably due to having a corrupted IIS Metabase table. You will also need a patch for the Profiler to stop the error occuring, which you can get by contacting support@red-gate.com.
There is now a workaround for this in ANTS Profiler 2.5. Any exceptions generated when reading the IIS metabase are caught and handled and the corrupt virtual directory should be excluded from the list of virtual directories.
This is problem is probably due to having a corrupted IIS Metabase table. You will also need a patch for the Profiler to stop the error occuring, which you can get by contacting support@red-gate.com.
I hope this helps