Faq & Trouble Shooting; Frequently Asked Questions; How To Make The Factory Reset; Upgrade Firmware Under Safe Mode - ATCOM AT820 User Manual

AT820 Series User Manual
B. Received: The recorder of the received calls, maximum 50 items.
C. Missed: The recorder of the missed calls, maximum 50 items.
6. FAQ & Trouble Shooting

6.1. Frequently Asked Questions

6.1.1. How to make the factory reset

There are two ways to make the factory reset:
A. Factory reset from keyboard，steps are:
1. Press soft key "MENU", input right password;
2. Find and select "Factory Reset" ;
3. Press "OK", then the phone will restart automatically and factory reset.
B. Factory reset through web, please refer to

6.1.2 Upgrade firmware under safe mode

If the phone could not start up normally, upgrade firmware under safe mode. Steps are:
1. Build a TFTP server and set its IP address as 192.168.1.200;
2. Copy the firmware to the root directory of the TFTP server and modify the file
name as AT820.FW;
3. Make sure the TFTP server and the phone are contacting with the same switch
and reachable to each other;
4. Long hold "#" key and start up the phone until the LCD display "Upgrading...";
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Reset & Reboot.
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