There's nothing wrong with your system to warrant that it is in need of replacement. It's just a glitch. I agree that failing power supplies can cause all kinds of strange activity, as can failing cards. You may end up trying the old process of elimination game with the cards.

The last time that I encountered this situation, it was because the COS settings had been changed to where CO to CO forwarding was not enabled. I have NO idea how that occurred, but once I enabled this, the problem went away. The system would allow you to enable/disable group forwarding, everything looked right on the display, but the group's intercept destination (mailbox) would answer. You might want to check the COS settings first.

Ed Vaughn, MBSWWYPBX