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Question: Why is one VoIP stuck as Unregistered?

Background: We have a Cisco UC540 Small Business switch/router/voip combo. This phone was working until I powered everything down to install a larger UPS unit. The phone originally had a status of "Deceased". I removed the registration and tried to add it again. Now it just sits as "Unregistered". I even tried giving it another extension.

I am stuck using the Cisco Communication Assistant since this is small business hardware. There is very limited CLI access. Also, from what I heard, if you access the CLI with out cisco permission, you will void any warranty.

The phone in question is a Cisco SPA501G. It is connected to a SG300-28P. There are 5 other phones on this switch working just fine. I have tried other ports with no luck. Both the link and PoE lights are lit up.

Debug logs attached at : a few screenshots at :

Interesting part in the Debug log is:

  1. tons of ACK timeouts.
  2. Bad sequence number with fatal error 254, msg header is -1.

this appears to be the phone trying to register:

000565: Sep  7 10:59:04.549: Received StationRegisterMessage from phone SEP0002FDFFE166,    sock 16
000566: Sep  7 10:59:04.549: TCB86BE8398 setting property TCP_TOS (11) 8A87B1C0
000567: Sep  7 10:59:04.549: ephone-(1)[16] Register StationIdentifier DeviceName SEP0002FDFFE166
000568: Sep  7 10:59:04.549: ephone-1[0/-1][SEP0002FDFFE166]:stationIpAddr
000569: Sep  7 10:59:04.549: Skinny register (phones=14/14/41) REJECT from IP

Any ideas?

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migrated from Sep 7 '12 at 9:09

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