Firmware downgrade

[donovanc]

I have a T22 which I am trying to downgrade from:
Version
Firmware Version 7.72.0.51
Hardware Version 5.0.0.61

To:
Version
Firmware Version 7.61.0.80

I am auto provisioning from a Broadsoft pbx which requires this specific firmware.

The upgrade process seems to be running for a minute or two, but after a reboot it is still on 7.72.0.51. I've tried IE, Firefox and Safari, but no luck.

I have experience the problem with T20 as well.

Anything I am missing?

[Yealink Support]

The 7.72.0.51 is the RPS version ,could you please help check whether you have configured in the auto provisioning about the upgrade syntax then upgrade to 51? and share us more information about the details.

and please let us know why you want to use the 7.61.0.80 , it is the very old commerical version not special version, could you please let us know the reason ? usually we suggest the customer use the latest commerical version which is more stable and support more feature and we don't maintain the old version.

[donovanc]

We use a broadsoft hosted pbx and the vendor requires this firmware for their auto provisioning to work properly. It does not work with the later versions.

[Yealink Support]

Hi,donovanc

I tested found to be possible

I suggest you try again, to ensure that the correct version of the firmware upgrade

Here is the Firmware Version 7.61.0.80 ，please check

ftp://Jim:v2R88xcL@ftp.yealink.com/%C1%D...1.0.80.rom


If it dosen't work, then you can put the process of upgrading the screenshot to me to see it.I can see where the wrong