After having no problems in the past with PSE 15 I now find that Edit will not always open. Sometimes it works, sometimes it doesnt. Any suggestions - Adobe tell me that it does not support PSE 15 by chat.
Sorry that Photoshop Elements 15 Edit does not work as expected.
Please reboot your machine once. And then while trying to launch Photoshop Elements,: Press and hold Alt+Control+Shift (Mac: Option+Command+Shift) immediately after Photoshop Elements begins launching. Click Yes to delete the Adobe Photoshop Elements settings file.