Scratchremoval.dll error

When I start PS CS3 extended I am suddenly getting an error message: "Thsi application has failed to start because scratchremoval.dll was not found. Reinstalling the application may fix this problem". The title bar of the message is "Photoshop.exe - unable to locate component"

Anyone have any idea why I would be getting this error message? What is scratchremoval.dll associated with?

Thanks.

It's probably a plugin that was installed and is now missing. Perhaps Polaroid's dust and scratch removal?

Rob