I have installed myEclipse 20050829-4.0.0-GA 4 months ago and it has been working very well. Now all of a sudden it refuses to build no matter what I do. I even deleted the old project and recreated the project and it's still not kicking off the build. I got the following build error:

Project 'WSP' is targeting a 1.2 runtime, but iscompiled against
'D:bea/jdk142_05/jre/lib/rt.jar' which requires a 1.4 runtime


What is this? There is no jdk1.2 or jre1.2 in my envionment. Where does that come from?

Open up your compiler settings and go to the "Compliance" section, somehow this likely got set to 1.2 and it should be 1.4 or 5.0.

Project Properties > Java Compilers *** IF you have "Enabled project specifi settings" checked here, make the changes here, otherwise click "Configure Workspace Settings" and make the change there ****

Thanks rkalla. You are right. That was exactly what happened. I found that problem and fixed it as you suggested but the problem still persisted. So I ran the magic command "eclipse.exe -clean" and that fixed it.

Glad it's working now, nice job using -clean, I'm amazed to this day the little quirks that seems to fix at times.