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The solution has been tested using:
Yealink T41P
Yealink T21P E2 E2
Browsers Google Chrome or Firefox
The information detailed in this guide is applicable to the firmware version 71 or higher.
The firmware format likes x.x.x.x.rom. The second x from left must be greater than or equal to 71 (e.g., the firmware version of SIP-T28P IP phone: 2.71.0.140.rom)
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