@Marari So I haven't tried it but my understanding of the phrasing is that if there is a firmware released AFTER the .55 release you won't be able to update from the console. Meaning .20 -> .55 should work fine but say .20 -> .75 (just making that version up) won't. A fairly common situation when there is a major firmware structure change. Just like the SPA phones where you have to update to 7.5.2 before going higher. Don't have any T29's to test but my T41P's upgraded just fine.
I bet if you look in the folder you'll see a patchT29 and then the full file. It's probably the same error as I'm getting on the T46
It's very strange, because one the T29G phones that I updated was behind the SBC too.@Aram
Thank you for the reply.
The problem is that while the "patch" script is downloading, I cannot get any of the T29's to update.
They are running behind a 3CX SBC talking to a Google Cloud implemented 3CX installation.
View attachment 8881

It's very strange, because one the T29G phones that I updated was behind the SBC too.
Please have a look and if you still have the problem, please contact to our Support.
Another idea: Are you trying to update all of them together? If so, please try one by one - probably it's a limitation from the Google Cloud.
The file sizes looks correct. Can you try to manually download the FW file from the 3CX PBX and try to update one of your phones manually?
The file sizes looks correct. Can you try to manually download the FW file from the 3CX PBX and try to update one of your phones manually?
The link will look like this: https://YOUR_PROVISIONING_URL/firmware/yealink/T29-46.83.0.55.rom
2. How the update works and why do you need to have the custom "patch" files.
To fix the mentioned issue the Yealink team provided us with the "patch" files that will use some scripts to disable the mentioned restriction.
When the user will perform the firmware update on the Yealink phones from the 3CX Management Console, 3CX will provide 2 files to the phone - first the "patch" file to remove the restriction and then the actual firmware file.
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In this example the phone will download the "patchT29-46.83.0.55.rom" file, it will remove the restriction, the phone will automatically download the actual "T29-46.83.0.55.rom" file and update.
we are seeing the same thing with our T46s connected via STUN. We've rebooted them and reprovisioned, they rebooted - thought they were downloading the firmware (red light was flashing) - but still no dice.
Hi cobalit,So how exactly is this part supposed to work? The config file generated by 3CX points to the patch file which makes sense given your explanation, but then how is the phone supposed to know to get the full file?
For the record we have a cloud-based instance with a SBC in our office. The T41P phones upgraded just fine but the T46G's will not. Going to try and switch one to STUN to see if it will upgrade.
Hi,we are seeing the same thing with our T46s connected via STUN. We've rebooted them and reprovisioned, they rebooted - thought they were downloading the firmware (red light was flashing) - but still no dice.
Hi bbaker73,I've just started on my systems, and seems the T46s (STUN) are the ones having the most trouble with this update. A few small systems did ok, but some do not. Can't seem to find rhyme or reason.
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