Followed the instructions in the link. First, did a search for desktop.htt. It came up empty. Did a manual search on the path included in the directions, and found three instances of desktop.htt--don't know why search couldn't find them. I did have the protected files unchecked. Anyway, deleted the three instances of desktop.htt, and rebooted. Problem persisted and, as predicted, desktop.htt was regenerated in the three locations.
Did a search again. This time it found the three files I'd deleted in the trashcan, but it didn't find the new, regenerated files. Any other thoughts?