Extract Huawei E397Bu-502 Firmware 11.515.15.02.1050.B757 on your computer
Install the Firmware update file for Huawei E397Bu-502 downloaded from Huaweiflashfiles.com
Follow the procedure for updating Firmware that is given in Package.

Huawei Flash File | Size: 13.81 MB
Version: 11.515.15.02.1050.B757
Operator:USCC USA
Operating systems: Windows 7/8/10/XP/Vista
Huawei E397Bu-502 Firmware Download