Never meet the issue before. How about uninstalling the BlueSoleil Bloototh.? Actually you can find a lot of answers for your question if you search on Google.

You may try to uninstall and reinstall the skype and League of Legends. Try the computer with skype and the game with another wifi signal or connect that computer to the modem by an Ethernet to do a...

There is a notify on the firmware website: Do NOT upgrade the firmware through wireless connection unless there is no LAN/Ethernet port on the TP-link device. Actually upgrade through wireless will...

There is much difference between the two routers. The antennas of TL-WR849N are also with RP-SMA connector. The TL-WR849N is likely a special version of TL-WR840N.

Perhaps your router was with UN version. There is no limitation for UN version to upgrade to US version.

You can contact TP-Link support. If it is under warranty, I think you can get a replacement.