Just added a windows 7 or Vista system to your 2003 domain? Well if you use scripts to map your network drives you will find that none of these network drives are available to the user after login. This is because the new security settings in windows make the user run as a normal user and not as an administrator.
To show how this works. Log onto a system that is experiencing this problem with this misery mapped drive. Now click on the start button and type in notepad. Before running it right click the notepad program that appears in the search results and right click on it. Run as administrator and notepad will open. Now click on File and open and browse to Computer and you will notice your hidden mapped drive is now available. This mapped drive mapped correctly but only works under the administrators' portion of the account not under the user.
Well, personally I recommend getting 2008 server and using the new map drive options and stuff. But if you can't do that then simply modify the settings on your vista, win7 box so the user account can see the mapped drives. The following is the changes that you will need to make.
Let me know if this helped someone out or not.