Have a customer with one of these systems about 4 years old. It has a modem on it but I don't know what (if any) software is needed (on my PC)to talk to it remotely. Anyone know?

Dane, if I remember correctly, the VX400 and VX800 were discontinued last century! They weren't Y2K compatible and Mitel decided to come out with something new, different, and exciting. I installed 2-3 in the mid-'90s, and they ran, as usual, on Mitel's own OS. And yes, you'll need special software. I haven't got it, and no suggestions on where to get it. Is this system a refurb, or has Mitel resurrected the name? John C.

This actually isn't a Mitel VM - it is a VX voice processor and is designated as a 400.