This forum is for the WNDR3800 and not the WNDR3700. Not only does the WNDR3700 have it's own forum, but the firmware is different. Netgear has pulled v126.96.36.199 from their servers and is listing v188.8.131.52 firmware as current for WNDR3700v2 owners.
Unfortunately, by upgrading your router's firmware to v184.108.40.206 it is no longer possible to use the conventional method of downgrading. Instead, you will now have to use TFTP to downgrade to the v220.127.116.11 firmware. Or, wait it out. Instructions for how to use TFTP are in the WNDR3700 forum.
_____ WNDR3700v1 (v18.104.22.168NA) - Router uptime (d:h:m:s): 1155:02:31:46 - How To Check and Change Your Router's Firmware: http://forum1.netgear.com/showthread.php?t=63234