Question : Folders Opens in new windows everytime

We have Windows Server 2003  
when we try to open a folder like (documents) it opens in a new window and happens to all folders.
they open on new window  and users get tired of closing a lot windows.
also  it doesn't let go back to the folder it was before  because its on another window
I've allready try to change the folder options from  (Open and Explore)  but its the same
is there anything i can change on the Registry?
thanks

Answer : Folders Opens in new windows everytime

Locate the Default value under the following key in the registry: HKEY_CLASSES_ROOT\Directory\shell Type NONE in the File data box, click OK, and exit the registry editor.