Unmapping a network drive

Does anyone know how you can UNMAP a network drive inside of a login script? For example, we have 3 different scripts that run, one general one, one group one and finally an individual user script, processed in that order. This way we customize whatgets mapped for different users.

Our general script maps a couple of drives common to just about everyone. The problem however is that now we are creating a few new users that we want to have a very restricted set of mapped drives and wanted to see if there was any way inside of either the group or user script that we could add a command that would UNMAP a drive that was assigned in the general script.

I appreciate any help that may be offered.

Mark Austin