Did you see this
http://www.perfectdisk.com/support/kb/835
Did you have the program installed at one time? Could be left of in the registry. Have your tried searching your registry (you have to be careful)
If all else you can try to reinstall the program and then uninstall it.
When trying to upgrade Vista 32 bit to Win7, I keep getting the following message:
The following issues are preventing Windows from upgrading. Cancel the upgrade, complete each task, and then restart the upgrade to continue.
For these items, make the following changes:
Uninstall these programs. Open Control Panel and search for "uninstall a program".
PerfectDisk
After searching my HD 5 times, this program does not exist on my computer.
Can anyone help? I did a web search and PerfectDisk is a defrag program recommended for Win7 per their website.

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