Click on the tiny arrow directly to the right of your name. In the drop-down box, select open other mailbox.
Type the name of the mailbox that was selected to act as a voicemail for this resource account.
IT Pros who set up the mailbox will have to make sure that they have given you permission to access the mailbox. There is no password or user name to input; you can just open another mailbox that you have been given permission to access.