I don't think you got the entire information from your customer. It worked, at first, that the phones could dial zero and 911, but they could never be transferred because you have blocked the interconnection to the guest phones tenant.

My guess is that the front desk could either hold or press the transfer key and get the guest, but when they would try and connect the two, the calls would drop.

You may want to consider a Viking Electronics TR-1 call restricter for each phone. You could put all the house phones back in the same tenant group as the guest phones, but still have only dial zero and 911 access. With them in the same tenant group, call transfer through the front desk would be possible.

Rcaman

Americom, Inc.
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