If your Cisco IP Phone is stuck and you suspect a repack issue, follow this checklist:
A valid XMLDefault.cnf.xml is usually 1KB to 8KB. If your repack has a 0-byte file, delete it.
If you are stuck on a specific deployment step, let me know: What are you trying to configure? cisco ip phone downloading xmldefault cnf xml repack
On the IP phone itself (depending on model):
If the specific file is not found, it falls back to this global default file. If your Cisco IP Phone is stuck and
Cisco IP phones often cannot upgrade directly from very old firmware versions to the latest releases due to changes in file signatures, file sizes, or memory allocations. When a firmware "repack" (a non-standard or combined firmware bundle) is uploaded incorrectly to the TFTP directory, or if the phone requires an intermediate "step-upgrade" firmware image first, the phone will fail to validate the new load, reject it, reboot, and request XMLDefault.cnf.xml again. Step-by-Step Troubleshooting Guide
A practical example from community forums involves moving a phone from CUCM to MPP firmware for use with FreePBX. The process uses a XMLDefault.cnf.xml file to orchestrate the upgrade: On the IP phone itself (depending on model):
If the phone keeps re-requesting XMLDefault.cnf.xml every few seconds, the file is likely . Check your CUCM version logs: RTMT > Logs > TFTP > tftp.log for XML validation errors.
If the TFTP server does not have a specific configuration file registered for that phone's MAC address, the phone falls back to request the global default configuration file: xmldefault.cnf.xml .
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