在Google搜索最近几个小时后，我找到了答案。
删除以下缓存文件夹：

C：\Users\yourusername\AppData\Local\NetBeans\Cache

它解决了我的问题。

I'm creating a new NetBeans EE Enterprise Application, and when I try to create Entity classes from database (Customer from the sample database), I can't select it because of this error :

Any idea? I'm using NetBeans 7.3 with Glassfish 3.1.2.

I found the answer after spending the last few hours searching in Google. Delete the cache folder in the following

C:\Users\yourusername\AppData\Local\NetBeans\Cache

It solved the problem for me.