Yealink T53w Firmware Upd Verified Here
Do not close the browser or power off the phone during this process. It usually takes about 5 minutes and includes two power cycles. Advanced Update Methods
Under the tab, download the .rom file. If it downloads as a .zip , you must extract the .rom file before uploading. Step 3: Perform the Update (Web Interface) This is the most common method for individual devices: yealink t53w firmware upd
Go to the tab and select Upgrade from the side menu. Do not close the browser or power off