Please connect an Ethernet cable between port 1 on the back of the Linksys and your computer.
Turn on the router and wait for a few minutes.
You will be prompted to log-in. The default username is "admin" and the password is "admin" (unless you have changed these).
Click on "Administration" on the top menu
Click "Firmware Upgrade" on the menu below.
Click "Browse" and select the firmware file that you have been provided.
Click "Start to Upgrade" and press "OK" to confirm.
The upgrade process will now begin and take up to 5 minutes to complete.