The only time I've seen JBuilder get braindead like this was when I had a badly damaged user.properties or project jpr/jpx file. I'd go into your {user.home}/.jbuilder4 directory, copy the user.properties file to a safe place, and then delete it altogether. See if JBuilder will launch and that it will create a new user.properties file.

I've also seen damaged project jpr/jpx files cause similar problems. The user.properties file contains a list of all open projects. You can copy the old user.properties file back but edit out lines which reopen projects. You may be able to track down which project causes JBuilder to kack, and from there fix that project's jpr/jpx file.

This is what I do to track down this sort of problem. I don't know that it will solve yours, it's just where I'd start looking. ~
2001-Sep-09 12:03pm gyles19@visi.com