I was foolish enough to accept a job of fitting 2 new extensions to a DK40i without delving into the full set up. It transpires that they have DID with the published number going to one group of phones and the DID number going to a second group. The new extensions are required to ring with the second group but so far I haven't got them to ring at all! I suspect I have to add the DNs to the group, but I can't find how to find the group identity. I'm sure if I read the manual long enough the penny might drop, but can anybody point me in the right direction, please?