cannot upgrade or downgrade from x.83.0.55 firmware

[kenhoosen]

(12-02-2019 08:31 PM)bardentech Wrote:  

(12-02-2019 08:26 PM)kenhoosen Wrote:  

(12-02-2019 06:22 PM)bardentech Wrote:  

(10-23-2019 03:36 PM)kenhoosen Wrote:  We are using 3CX and have recently updated 3CX to version 16. We have several Yealink phones that are on version x.83.0.55 firmware and 3CX states that this version is unsupported. When I attempt to update the phones to a more current firmware, I get a firmware update failed message. To troubleshoot the issue, I have tried both upgrading and downgrading the firmware but, it fails every time. Phone models that we have this issue with are T41S and T21P_E2.

Anyone else have this issue (and possibly a solution)?

Thanks.

I'm having this issue right now. Did you get it resolved?

Yes. See the previous reply from mujizac.

I did see that. However, that solution didn't work for me. As it turns out, 3cx was downgrading the firmware back to 66.83.0.55 after I manually updated it to 66.84.0.35. I had to first use 3cx to upgrade the firmware, which it wouldn't do but it would provision it to receive it after the 84.0.35 upgrade was manually done.

I would try the following in order:
1) Remove the phone from the extension within 3CX (so 3CX does not try to automatically provision the phone).
2) Do a factory reset of the phone (by holding down the OK button for a few seconds, and then the display will appear warning "Reset to Factory", press OK again to confirm the reset.)
3) Manually load the 66.84.0.35 firmware.
4) Update to whatever firmware version you are trying to go to.
5) Add the phone to the extension and re-provision.