If PowerDB Lite or Advanced Editions will not start up or you get a message "Validating database" that does not clear over time, this likely points to a corrupt database file. This issue is easily resolved by deleting the database file and restarting the application. The file, pdblite.mdb, once deleted restores itself again when you restart Lite or Advanced.
For users of Windows XP, the file pdblite.mdb can be found in one of the folders:
C:\Documents and Settings\yourusername\Application Data\Optima Systems Inc\PowerDB or
C:\Documents and Settings\yourusername\Application Data\Optima Systems Inc\PowerDB.v10
For users of Windows Vista or Windows 7, the file pdblite.mdb can be found in one of the folders:
C:\Users\yourusername\AppData\Roaming\Optima Systems, Inc\PowerDB or
C:\Users\yourusername\AppData\Roaming\Optima Systems, Inc\PowerDB.v10
If you cannot find the file on your PC, use the Windows search feature found in the start menu to run a search for files that match the filename pdblite.mdb. Delete all instances of the file that are found. Then restart PowerDB.