Voice Mail set up but won't pick up

In the link

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Manual

Dtu-16D-2 Tel - NEC Electra Elite IPK II System ... - ManualsLib

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NEC Electra Elite IPK II Manual Online: Dtu-16D-2 Tel. This digital Multiline Terminal has 16 programmable line keys (each with a 2-color LED), ...

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  NEC 16D and 8D Quick Start User Manual - ManualsLib

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  View and Download NEC 16D and 8D quick start user manual online. Multiline Telephone. 16D and 8D telephone pdf manual download. Also for: Dth-32d, Dth-16d, ...
  
  

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You need a laptop hooked up to the vmail system and or do via from telephone form system mangers mailbox.
You should be calling your vendor who handles the system, this is complex and involves passwords and which mailbox was assigned SM etc.
They vendor can also supply you with guides.

If you are using an Active Voice product (typical w/ NEC) you need to change the hours of operation on the voice mail system. "Night Mode" only changes the ringing characteristics of the phone system and where calls ring, not the greetings that play on the voice mail. The voice mail plays a particular greeting (Day/Night/Holiday) based on the time of day specified in the schedule. The system administrator for the voice mail would have to make this change.

Set your Call Forward Busy/No Answer to go to voice mail ext. as follows: Lift the handset, dial 4 then 3 followed by the voice mail ext. (the number you dial to retrieve voicemail messages). Hang up.

Cleared voicmail on all other extensions and waited, it eventually (3hrs later) cleared itself

We would first need to know what system you are using. Look for the system in a telephone closet or server room and their should be lettering on it, like ivs, ipk. Let us know what it is, than also there is a card in the system thats has lettering on it like vms, fms, vmp we would need to know what type of card as well to tell you how to access it. There could also be an external device, like pc, hooed to the phone system to run voicemail, but we need details. check out ldtsnj.com

hit feature key,hit a line key,dial 9 plus the number,hit feature

The call forwarding was turned off. To turn on, press speaker, enter 793, press 1(for set), press extention number, and enter 300. If you have call forwarding on and are looking for more rings, do the above steps except press 2 (for clear).

It sounds as if that particular extension is in Do Not Disturb.
From that phone, try Feature - 69 - Feature.

Jennifer209, if you press FEATURE + the button VM is pre-programmed on what does it display? It should show the extension number pilot to VM. If you call it directly, what happens? If you get no answer calling it directly, your VM may be down.

Kaait, is it getting into the VM that's the problem, or doing things inside the mailbox that is the problem?