Failed to create the part's controls in Eclipse with Salesforce

Question

I have Eclipse Juno and Force.com IDE. When I try to create new classes they always show: failed to create the part\'s controls. It worked for the first tim

Answer 1

I had the same error. I fixed it by switching the eclipse workspace. Go to menu File->Switch Workspace->Other, and then select the same workspace you were working with. Eclipse will restart and you should not get the error.

Answer 2

I got the "failed to create the part's controls" error one day when I opened Eclipse and tried to view a java file I had been working on. When I opened the file I needed, it showed a red X and NullPointerException instead of the code. The error log mentioned "event loop exception" for some reason.
I restarted Eclipse, and the error was still there. I cleaned the project, updated the project, deleted and re-imported the project, deleted and re-imported the file, and the error still was there. As a last resort, I restarted Eclipse again and then the file was fine. So one of the clean/update/delete/import steps worked but I don't know which one.