Disable a users voicemail feature in Lync 2013

The Unified Messaging Service (part of Exchange 2013) provides voicemail functionality to Lync users. So in order to disable voicemail for a user you can go to the ECP on which the Exchange Unified Messaging Service is installed select the user from the "Recipients" menu and then click on "Disable" under the "Phone and Voice Features" >> "Unified Messaging" section on the left hand navigation view.