Try Making sure:
\documents and settings\xxx\application data
\documents and settings\xxx\local settings\application data
\documents and settings\xxx\application data\microsoft\installer
and, if it exists, \documents and settings\xxx\local settings\application data\microsoft\installer
All have sufficient permissions. If you’re unsure, try giving “everyone” full permissions. If you feel there are security issues, you should try this to determine if it’s a permissions problem, then remove “everyone” and narrow down from there. You could also just add “everyone” to the entire documents and settings folder, just in case.
Try uninstalling (make sure you delete the pixologic folder in program files), changing the permissions of the folders listed above, then reinstalling.