I have a PRI 24ch. Was running 4.1.(17) upgradeds to 4.2.(20). Everything seems to be working well and the next day I get a trouble call. Can't dial out on all 24 trunks. I checked all against the original config prior 2 upgrade. Incoming calls working OK. Get a fast busy tone when dialing the complete 10digit string plus 9 code.
Working with ATT now. They say they see T1 and channels OK. Going to have someone trap some calls to assist.
Any ideas!!

Trouble solved!!!!
ATT tech support assisted. Found a problem bug with this 4.2.(20) release. Outgoing calls were in an invalid format. One fix would have been to change switch type to unknown but that isn't an option in IPOffice. The solution was available in Avaya IPOffice tips #212. In NoUser Source Numbers add NI2_CALLED_PARTY_TYPE=UNKNOWN.

Fix one break another!!!
The client has 2 T1s. Line1 is PRI from ATT telco. Line2 is interoffice T1 between Magix and IPOffice systems on the property connected via a fiber RAD FOM E1/T1. I fixed the outgoing calling on the PRI but now the interbuildng calls are broke. I cannot four digit dial across the T1 bothways or transfer calls without dialing out and back in.

Try 4.2.23 and see if you can take the called party type out.