We have a customer who has a NEC DSX-40, they have an SLT extension (350, durafon) that rings when calls come in on the line, but when someone tries to intercom call, or transfer a call, it goes straight to voicemail.

I can make intercom calls via the handset as well (though I have to wait a long time for the tone to change before it will go through)

I'm not an expert on the NEC or durafon system by any means, so I'm hoping someone here can help me find what setting on either the durafon or the phone system is not correct. The biggest thing that we really need to figure out is the transferring/intercom.

Try going off hook with the Engenius phone & dial 7470 - This will cancel any DND services - the user may have inadvertently dialed 7472 without dialing "9" for and outside line which would activate DND for intercom calls only.

I just heard back from them, that didn't change anything.

Did someone check that mailbox for "auto attendant direct to VM"?

Where would I find that setting? And is it station/extension specific?

All of the other extensions/stations work as expected, it's just this EnGenius durafon that's going straight to VM.

It is station based, and a inmail option. It can be set or cancelled by the user.In the inmail assignment for the mail box.

Check the SLT extension coming out of the system with your butt set to eliminate the system first. If the system is good, call EnGenius Tech support they're pretty good at walking you through Programming.

I checked that, it's not set for the extension

I'm pretty sure it's good because calls do ring in on it, it's only transfers that are going straight to voicemail. And he can call out on it, if he waits like 15 seconds for the dial tone to change sounds.