Do you have any daughter cards attached to the card in question, you really should not have to A: Mess with 10-09 or B: reset the system.
I know its frustrating.
When it went from 1.?? to 2.0 there was issues with DTMF tones going to the Voice Mail slow tones, no tones and then it would affect the whole system particular anai's. Only had it happen to 2 systems . Release 3.10 is out plus it adds on 4 FREE IP Phone Station Ports.
I see that in your post you said.." the main customer"...is this system Netlinked or anyting else going on esides a solo system? Plus What is you port count compared to what your system is licensed for? Now that I think about it we had 1 system that would lose phones, etc ,reset everything ok, 1 time it lost its license it would show they were there but if you went through the phone programing mode they were not , Had to intialize system and reload license file. This last one is a real reach but,sh#t happens that we just cant control. Sorry so lengthy

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