Do you have any USB 3.0 devices connected to the router? Or any 2.4GHz interference sources around your home? Please try to find a solution from the FAQ below:...

May I know the file system of the 128G USB stick? Will it detected by a Windows computer? If you don't have too much files in the drive, you can backup the content on your computer, and then format...

It seems that your firmware version is already our of date. Have you tried to upgrade to the latest one on the official website? http://www.tp-link.com.my/download/Archer-C7_V2.html#Firmware

May I know what's the connection type? Is it PPPoE? It's recommended to post the system log here for analyzing.

Hi All, [COLOR=#333333]Solutions for different versions (download link), hope they will help you! [COLOR=#333333]Archer C7 V2 [COLOR=#333333]US: http://static.tp-link.com/resources/...up(160511).zip...

If you insist the bandwidth control for guest network, you can flash back to the previous firmware version. Archer C9_V1_151125