SPA514G stuck on Firmware 7.5.5

[ger-lynch1]

Hello, 

I have a SPA514G phone and I upgraded the firmware to 7.5.5. For the most part the phone is ok nut at times it can be a little buggy, for this reason i want to change it. Ideally I would like to go back to 7.5.2 as this was the previous version and I had no issues with this. I cant get the phone to downgrade its firmware.

I tried setting up a http server to serve the files to the phone, the phone receives the firmware file but instead of writing it to memory it just reboots and comes up with 7.5.5 again.

I tried using the windows tool in the zip files from the Cisco firmware site, This does the same thing. It connects to the phone via IP address and uploads the FW file, then the application says "Please do not unplug your phone while the status light is blinking". The status light never blinks, the phone just reboots after it receives the FW file and comes up with FW 7.5.5. I tried the recovery tool also but it asks for the phones Serial number, It will not connect to the device this way though and it fails after a short search. 

Is there any way to change this FW version, why cant i get it to write the file to memory? Also for the record, I have tried this with multiple FW versions from 7.5.2 to 7.6.2 

[Dan Lukes]

It's not as easy.

1. Downgrade is unsupported procedure, unless advised by Cisco's support.
2. Your device may become bricked by downgrade. To lower the risk, never downgrade configured device. Reset it to factory default first.
3. Hardware revision of the device needs to be taken into consideration. Most recent hardware revisions may not be supported by old firmware releases. I'm unsure that there's <7.5.2b firmware that can be flashed to SPA51x.
4. Remember 7.5.2b firmware barrier. It can be crossed in one step in no direction. Upgrade/downgrade to 7.5.2b first - it's mandatory intermediate step. To be on safe side, reset phone to factory default again when running 7.5.2b - especially if you are going to downgrade it beyond 7.5.2b

If you are still unable to flash firmware, turn on syslog&debug (highest level) and catch messages. It may disclose you the cause.

 I tried the recovery tool

Recovery tool can be used when phone is in Recovery Mode only. E.g. on phone with no valid firmware image flashed inside.

[ger-lynch1]

Thanks for your reply. It gave me a few options to try. 

I used wireshark to receive the syslog messages from the phone and tried using the Cisco tool for changing the firmware. (Please find attached the Wireshark screenshot to show what happens here)

I tried this with a couple of different versions. I keep getting the same result! I believe the phone receives the file as it shows a progress of the file being downloaded and this matches with the size of the bin file in the directory. The only thing i can see is the file is not named spa3707.bi1 in my directory but would this matter? 

Do i have any other options to change the firmware? 

[Dan Lukes · Accepted solution]

Your's device current magic value is KoSmOsX FiRmWaRe (the SPA51x magic) while you are trying to flash firmware with different magic: SkOsMo5 fIrMwArE (the SPA30x/SPA50x magic).

So everything is clear now - you are trying flash SPA50x firmware into SPA51x device. Sorry, it's not possible. You need to download & flash SPA51x firmware into SPA51x device ...

[ger-lynch1]

Thank you, this solved the issue, I never realized  there was separate SPA51x. Thankyou for your help