I tried to swap two phones (using a dummy MAC in the process), but I'm running into the following error. I've tried tracking down the device in question but with no luck. I'm using Cisco Call Manager 4.1(3)
"The MAC address you entered is already assigned to the following device(s):
Please check the MAC address for each device and make sure it is correct."
That device name looks like a UDP - if you convert phones to UDPs, they get the username_phonename format. I'm guessing 3133 is a user that had SEP001818FD515CC associated.
At any rate, check under Device/Device Settings/Device Profile, I guess that UDP must refer to one of the phones you are renaming in some way?
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