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T42S unable to update firmware
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complex1 Offline
3CX Adv. Cert. Engineer

Posts: 1,403
Joined: Jan 2014
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Post: #5
RE: T42S unable to update firmware
(09-29-2022 07:45 PM)oliv Wrote:  I tried to update a T42S from to using web interface.
I followed the steps bellow:

1. download file from Yealink web site
2. select downloaded file after clicking over Browse button
3. click over Update button
4. observe a message like Updating firmware over phone's screen

After 15 minutes, I pulled the phone patch cord and replugged it: it restarted with version.

1. Which 66.86.0.x version shall I target first ?
2. Which 66.86.0.x version shall I target after the first one reached ?


The steps you are taking are good.
Devices with v85 firmware can be upgraded directly to firmware v86.

After the firmware upgrade is complete, you may want to check that the phone actually has the latest firmware before removing and reconnecting the phone patch cord.

If the phone contains the correct firmware before the restart, the problem lies in a remote firmware update via RPS that provides the device with the older firmware v85 again.

Kind regards,

I am not an employee of Yealink.
Dutch is my native language, not English. Apologies for my imperfect grammar.
Please do not send unsolicited PM messages. I will not answer them.
09-29-2022 09:50 PM
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Messages In This Thread
RE: T42S unable to update firmware - oliv - 09-29-2022, 07:45 PM
RE: T42S unable to update firmware - complex1 - 09-29-2022 09:50 PM
RE: T42S unable to update firmware - oliv - 09-30-2022, 02:29 PM

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