I have a 7960 with a 7914 module. This is set up with a primary line (not shared) and 4 shared lines which are on the module.
When the message button is pressed it does not pickup the primary line but a line on the 7914, and as such the user is trying to access the incorrect mailbox!
I have taken this line off and it selects the next shared line on the module!
When doing this there was no mwi on the primary line but the message icons where on the shared lines.
If I press * after the message button then I can access the correct mailbox.
I understood that when the message button was pressed it dialed Unity via the primary line unless a voicemail profile stated otherwise and there is no such profile in use.
If anyone has any ideas/thoeries or even a solution on this I would be more happy to hear them.