Resetting the Netbeans Userdir
By kishm on Jan 16, 2008
At times your IDEs userdir gets corrupted and this results in the IDE behaving weirdly like
1) In the New Project dialog, sometimes only a few of the categories are listed.
2) Your Project does not open properly, you get errors like "Project Folder Already exist" etc
3) You get an exception window on IDE startup etc.
To fix such issues, run the ide with a fresh userdir.
To do this, Delete your userdir entirely, restart NetBeans, and allow it to generate a new userdir from scratch.
This "reset" should repair the problem. For more on userdir, please refer to http://wiki.netbeans.org/wiki/view/NetBeansUserFAQ#section-NetBeansUserFAQ-Configuration