Had a 200 ICP that couldn't get dial 0 or priority dial 0 to go to anyplace but the console. Was trying to get room phones in Tenant 1 to go to a cordless phone in tenant 2. All tenant interconnection was correct. It double and triple checked everything but no go. Spent hours being stubborn. Finally just moved a room into tenant 4 to test and it worked. Nothing different. Don't know if there was a bad spot on the disk or some other kind of corruption.

Worth trying if you run into the same situation.

(and yes I did try taking it all out and putting it back when I was checking)