To Test DNS Root fails because the root DNS blocks Ping and it won't affect internet access actually although it shows Fail? If there is any problem, you'd better describe the problem in details. :)

Did you try chipmaker's driver (Realtek RTL8192CU)? http://www.realtek.com.tw/downloads/downloadsView.aspx?Langid=1&PFid=48&Level=5&Conn=4&ProdID=277&DownTypeID=3&GetDown=false&Downloads=true Some...

TL-WA901ND has no such a function in range extender/repeater mode. WA850RE can make it.

Sas, did you check the Wi-Fi name and password on web interface of WR1043ND after upgrade? The NAS can detect Wi-Fi signal but cannot connect? Password is required? Any error message?

The speed of wired connection to WR841N is normal or not? Channel width is configured as 40MHz? What's the connection speed getting on wireless clients? To figure out if a specific router is abnormal...

TL-WR841N? To change login username and password, on its web interface, you can go to System Tools---Password. To change wireless username and password, first, go to Wireless---Wireless Settings to...