How are you assigning groups? I assume you are going to assign them by either NT groups, by passing a variable from the calling .bat file, or by user lists.

You can use the INGROUP function to see if the user is in a certain NT group and assign them drives based on that. Are there any drive mappings assigned to everyone?

If you could post a sample list of users, what groups they're in, and what drive mappings each group needs to get, then it may be easier to show you ways it can be scripted.

Brian