Temporarily change the default browser to IE.
I tried that and still get the same error message. Very frustrating. It might be helpful to note that the Photoshop Elements that I have came with a camera in 2006. But the last modified dates on the files is 2001. I installed it in XP mode ok. Maybe it just isn't compatible with Win 7.
PSE10 works fine on W7; so you must be talking about an earlier version?