NOTE: You will require firmware version V188.8.131.52_1.0.1 or below in order to continue. Please download this version and downgrade your firmware to this version if required.
The Netgear R6220 requires a manual upgrade as the web interface does not accept the new firmware. However, this is straight forward.
Enable debug mode by clicking http://192.168.1.1/setup.cgi?todo=debug (username: admin, password: password by default). You will see "Debug Enabled!"
Use PuTTy or a similar terminal problem and connect to 192.168.1.1 via telnet on port 23. Login with "root". You are now connected to the command line. Type each below command one line at a time.
- cd /tmp
- wget http://router-firmware.s3.amazonaws.com/ng-r6220-kernel.bin
- wget http://router-firmware.s3.amazonaws.com/ng-r6220-rootfs.bin
- mtd_write write ng-r6220-rootfs.bin Rootfs
- mtd_write write ng-r6220-kernel.bin Kernel
The router will now reboot and within 5 minutes should be ready to use as normal.