My license is going to expire very soon, I will change my anti-virus software to Avast if there is no resolution before that. Seriously, very disappointed if ESET unable to fix this problem.
I also encountered the same problem which unable to access the Asus' router admin page. I also own both Asus RT-AC66u and USB-AC53, running Windows 7 64bit with Eset SS version 7. I can access the Asus router admin page using iPad without any problem.