First thing I'd suggest is to look for any anti-virus in your system that is not letting your NetBeans create any new Project.
You can try :
1 Disabling your anti-virus and try again.
2 Installing IDE in any other Drive except C Drive.
3 One more method but it is bit complex
Step 1: See if you can create a new project in a folder that doesn't
exist yet. Suppose the IDE does make this new folder for you, starts
filling it with files, then stops unexpectedly and says that 'Project
folder already exists, etc'.
Step 2: Look inside the folder and try
to locate the main class for your application (e.g.,
C:\NetBeans_Projects\MyNiftyJavaApp\src\myniftyjavaapp\MyNiftyJavaApp.java)
- Step 3: If the main class file does exist but is totally empty (0
bytes in length) it might mean that something prevents the IDE from
filling it with automatically generated code (as happened to me
because of the invalid main class template).
Last thing you could do is upgrading your NetBeans version.