With PT closed, copy that file, ptrack.mdb AND the hhdb.mdb file from the c:\program files\poker tracker v2 folder and put them into another folder for safe keeping.
Now, use the Start > Settings > Control Panel > Add or Remove Programs window to uninstall PT.
Reinstall PT...
http://www.pokertracker3.com/products/PTH/download.phpCopy the ptrack and hhdb.mdb file from the folder you put them in and put them back in the c:\program files\poker tracker v2 folder replacing the ones put there by the install program.
See if you can open the replayer now.
If so, send me a PM with the new product ID from the Help/About Poker Tracker window and I'll send you a new code.