My IP550 was running 3.x SIP software, and I decided to upgrade to the newer 4.x software. Part of what prompted this is that the provisioning host previously used no longer exists, and I didn't have my current configuration files, so I decided to start over.
Steps taken:
1. A new, empty FTP root was created, and the phone settings updated to use the new host.
2. I extracted _only_ the contents of https://downloads.polycom.com/voice/voip/uc/Polycom-UC-Software-4.0.15-rts22-release-sig-combined.zip in side of it.
3. I observed the new SIP application being downloaded, but after it self rebooted, this process would repeat indefinitely. I checked the logfile it uploaded, and saw a "Error: file does not contain a compatible image" error.
4. After googling my error message, I read that an "Upgrader" was needed for the upgrade to 4.x UC software to work. That led me to downloading this: http://downloads.polycom.com/voice/voip/uc/SoundPoint_IP_BootROM_4_4_0_Upgrader_release_sig.zip
5. I extracted the upgrader, noting that BootROM images were contained within.
6. After rebooting, I observed the BootROM update process begin. Shortly after, the phone now continually cycles every few seconds displaying:
"Primary Image Corrupt!
Reflashing Image from Backup!"
This cycle repeats every few seconds, along with various LED light patterns. No buttons appear to offer any sort of response, and I can confirm from provisioning FTP that no activity is occurring (no logins, file fetches/uploads, etc). Removing power and re-applying, it immediately returns back to this error message, self-restarting every 5-10 seconds.
How can I recover the phone?