I dial *90 to set up "Call Forwarding Busy", add the destination (rollover to another of our Comcast numbers) and am told the feature was successfully added. But it does not work. I don't see any mention of this issue in the Forumand I can't figure out how to login in online to manage it.
*90 to activate CFB and *91 to deactivate CFB should work fine. Are you testing it by calling your #1 TN and then staying on the #1 TN and calling #1 TN again to see if it is rolling over to the TN you want it to do so? Also when you entered the #1 TN CFB TN did you enter a 10 digit TN? Lastly, you should be able to also log into your online Digital Voice Portal and check to make sure this is setup correctly as well.