I am using the Panasonic Maintenance software program via usb to connect to the phone system. I've try programming a button as a dss button - voicemail transfer to extension number, which does not work. I've also attempted to program it as a speed dial which in my case is the first port of the voicemail extension - 150 plus #6, follow by the extension. When I try to transfer it does go to voicemail, but not the box itself. Thanks for all the help.