When I try to log into pl/sql developer, I get a blank error window with an Okay button. No other information. When I click okay, it takes me back to the login screen.
Maybe this is an environment problem. Can you start PL/SQL Developer without connecting, go to Help > Support Info, press the 'Copy all pages' button on this info screen, and paste this text into an e-mail reply?
Was this resolved? I have a user that has this problem on their laptop running XP Professional and PLSQL Developer version 7.1.5.1398.
I checked the Create global objects properties and both administrator and the user's ID is in there.
Hmm.. well, upon further examination, my user had (somehow) installed an old version (5.0). So...we uninstalled it and then installed 7.1.5.1398 and now it works great.