If you have an Asus WiFi router problem like; NAT / port forwarding not working, connection problems, upgraded to a firmware which caused your router to not work properly here is what you can do to solve the problem.Upgrade to AsusWRT Merlin firmware if you can find your router in the list of available firmware files. This firmware will probably solve your Asus router problem in 99% of cases.

Asus RT-N66U Wireless Router with Fresh Tomato VPN Firmware 2020.3. $50.00 +$20.00 shipping. Make Offer - Asus RT-N66U Wireless Router with Fresh Tomato VPN Firmware 2020.3. ASUS RT-N66U Dark Knight 450 Mbps 4-Port Gigabit Wireless N Router. $45.00. Free shipping. [IPv6] RT-N66U Firmware 5517 kills V6 - Comcast XFINITY Jun 20, 2014 Enable MESH for many ASUS routers, AiMesh | AnandTech Dec 17, 2019 Asus RT-AC66U 802.11ac router review: Latest firmware

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The ASUS RT-N66U Dark Knight is a slim and stylish 450Mbps 5GHz/2.4GHz concurrent dual-band 300,000-session Gigabit wireless router. Using powerful signal tuning and detailed setup, it offers stable and fast networking. RT-N66U BIOS & FIRMWARE | Networking | ASUS Global

A router firmware update goes bad | Computerworld

ASUS RT-N66U - TomatoUSB firmware Flashing Guide Mar 11, 2012