Indial Devert to Voicemail Without Mailbox

[HASAGO]

BCM400 R4.0 has indial number that forwards to vociemail but does not have a mailbox. This mailbox goes to a specific mailbox by default and I am wondering how it determines the default mailbox? This also happens on an
un-intialised mailbox. It does not go to the General Mailbox but to a normal user mailbox by default. Can I change this default setting?

 

[chiden]

It is probably set as alt ext in programming for a mailbox. So more than 1 extension goes into that mailbox. Couple of ways to find which mailbox number that extension is going into.
1-Do system report through browser. Find Extension.
2-Dial extension. When it answers pay attention to what is ON display. Not what you hear.
Now go into Telset Programming. Press MBOX>CHG. Now Press DIR. Enter name for what you saw on display. In Mailbox it will show you the main mailbox associated with mailbox as well as any alternate extensions.