Photo Stitching (v3.1 Win 7)

I have PhotoStitch 3.1 on my Win 7 PC. I tried putting three digital images from my Rebel into a panorama with Merge/Panning. Access to PStitch.dat was denied. If I burrow down into folders, it is in the right place with 0 bytes. The access is for anyone.

I did a little Google work, and found an interesting site with a similar post on a site for MalwareBytes. A respondent mentioned a possible virus, and suggested using CCleaner. It seems doubtful there's a virus involved.

Comments?

BTW, I have a digital Rebel from about 2004. Solved the problem PhotoStitch is for 32-bit OSes. Since the s/w was introduced years ago, they no longer offer it with newer cameras.