How to Reset Sangfor M5100-F-1 Firewall

To build a test network environment, a decommissioned Sangfor M5100-F-1 Firewall required to be reused. So, it needed to be reconfigured.

How-to

1. Prepare a USB drive and format it to FAT32.

2. Create an empty text file in the root directory and name it exactly reset-password.txt.

3. Insert the USB drive into any of the front USB ports on the M5100-F-1 and restart the device.

4. Once the device boots up normally, it will reset the administrator password and create a log file (reset-password.log) confirming the reset on the USB drive.
   

   Thu Jun 18 13:31:06 CST 2026

   
   

   new WebUI password is:username:admin,password:admin

5. Log in to the Web GUI with the default credentials, remove the USB drive, and change your password for security.

   • Connect to the firewall at the port - MANAGE

   • Assign a static IP to your computer

   • IP Address: 10.251.251.10 (or any address from .1 to .250) /24
   • Default Gateway: 10.251.251.251

   • Visit https://10.251.251.251

   • Log in using the default credentials:

   • User: admin
   • Password: admin

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