When mapping a network drive, if you receive an error message similar to the following: "Multiple connections to a server or shared resource by the same user, using more than one user name are not allowed", you may find the following Microsoft support article describing possible solutions to the problem: http://support.microsoft.com/kb/938120
This command will list out all of the available network connections for deletion. After reviewing all of the current network connections, you can confirm any network connections to delete. Once these have been deleted, you can then re-establish the network connection with the appropriate user credentials!
However, this solution is a bit difficult and tedious, but fortunately, there is a readily available improved solution to this problem. You can simply use the following command:
net use * /delete