This article explains how to repair TR905 firmware using the Device Rescue tool to resolve an Authentication Failure error.

Before you begin

You will need the following equipment:

Computer

Ethernet cable 

1) Verify that the clock is not connected to a power source.

2) Connect the clock to a PC using an ethernet network cable.

3) Temporarily set the local PC IP address to 192.168.1.220. 

To avoid interfering with any existing computers in a production network environment, use of a standalone PC is recommended.

4) Run tftpd64.exe and allow Windows Firewall permissions.

5) Run DeviceRescue.exe. 

A Command Prompt window will appear with constant pinging.

ping 192.168.1.201 TimedOut

ping 192.168.1.201 TimedOut

ping 192.168.1.201 TimedOut

ping 192.168.1.201 TimedOut

6) Connect the clock to a power source using its power adapter; the clock will turn on automatically.

7) Wait a few minutes. Command Prompt will eventually display "Successful operation," which means that the tool successfully transferred and extracted the repair package.

8) The clock will reboot automatically. If repair was successful, the normal home screen will display and no "lang error" or "authentication failure" messages will appear.

9) Disconnect the ethernet network cable from the clock.

10) To repair additional clocks, close DeviceRescue.exe and then repeat steps 1-9.