Photosmash plugin upload problem in only one blog

I installed photosmash and it is functional on all the blogs/subdomains except one. On that particluar blog, it does not work correctly. The photosmash plugin has a feature whereby users of a specified level can upload photos into a gallery. The Gallery page has a "Add Photo" link. It works on all my subdomains/blogs except one. They all use the same theme and set of plugins. I can't figure out the difference. I even deleted and rebuilt the subdomain site from scratch. It initially worked then quit. I get the following message: "Not Found Sorry, but you are looking for something that isn't here." The only thing different on this site that I can think of is that I imported content from a predecessor WP stand alone site. I looked at the threads on plugin's site but they didn't seem to apply because of the functionality on my other subdomains and because jquery.js was present. Anyone know of a solution?