From a campus phone with UM:
Press * to exit the mailbox for the phone.
Enter your 5 digit extension.
Enter your pin, then press #.
From a campus phone without UM:
Enter your 5 digit extension
Enter your pin, then press #
If your campus extension is call forwarded to UM, you may simply call your extension (5 digits on-campus or 7-10 digits off-campus), let it forward to your UM mailbox, then press *. You will hear your name, then a prompt to "please enter your pin, followed by the # sign").