Well the Voicemail is a separate unit, and the 8012 is a telephone. There's a manual link above that will most likely have what you need, But are you looking for a users guide for the phone or a service manual for the voicemail. If you answered Voicemail you'll need to see what voicemail unit you have. (it should be near your Comdial control unit) probably in some telephone closet with-in your building. I'm not sure if the voicemail manuals are listed in the manuals section. dtmf would know and I'm sure he'll chime in.

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