Have a NCP500 with some BRI2 cards setup to allow 4 PCs to dial out via ISDN modem to remote systems for programming access. Worked ok for a number of years until recently, now all calls via a modem connected to an ISDN extension are closed by the telco with the Cause Value= "#79 Service not implemented, unspecified". No changes to the NCP config or the ISDN BRI that I am aware of. Can dial out using a digital phone on the BRI with no issue.
Can anyone offer any clues to what to look at?
Can anyone offer any clues to what to look at?