Just a heads up to anyone considering a purchase of Premiere Elements 4.0 who also has Photoshop CS2 installed. After installing PE 4, Bridge will respond with the following message:
"Adobe Bridge cannot be used at this time because of licensing restrictions. You must have installed and launched at least one other Adobe application to use Bridge."
I tried removing PE 4, reinstalling Bridge, and Photoshop, re-activating the license, using System Restore in Windows . . . nothing worked. Finally called Adobe support. They are working on the issue, but do not have a fix at this time.
Only Bridge seems to be affected, the rest of Photoshop appears to work OK. Photoshop CS3 users do not report any issues.