Did you check “Use default gateway on remote network”? If IP Address pool is in the same range of LAN IP address, it should be Okay. But if IP Address pool is in different range from LAN IP address...

You can try to update the driver or reinstall the driver for the network card on PC 2. Did you get a chance to type in username and password when you try to login web interface of W9980?...

The software may not be able to run properly on Win 8.1... When you cannot access internet, there is Internet IP address under 3G? Try to ping google.com and ping 8.8.8.8. Maybe it is a DNS issue. On...

Go to Start, type in msconfig in Search Box and press Enter. Check if you can find TP-LINK Wireless Configuration Utility. Disable it.

PA211 and PA4030 are compatible with each other indeed. It will be fine to connect Router toTL-PA211, and TL-PA4030 to TV & BluRay. But the rate between them is limited by PA211.

Did you enable telnet client before you test it on your PC? http://social.technet.microsoft.com/wiki/contents/articles/910.windows-7-enabling-telnet-client.aspx To downgrade the previous firmware...