I have a TP-LINK TL-WN822N Version 3.0 that I was having some problems with on Mint 17, it worked but the internet was very slow (under 4Mbps) so I used an alternate adapter and that was fine. I recently broke my install so I decided to do a fresh install of Mint 17.2 and found that the TP-LINK adapter connects to my network but doesn’t actually allow me to use the internet so I decided I would finally sit down and try to fix it.
After some poking around I figured out that my adapter uses the RTL8192CU chipset* and after searching around for a wifi fix I stumbled upon this github repository, I followed the installation instructions on that page and my wifi adapter now works 100% at full speed.
*Do note that versions 1 and 2 of this adapter use an Atheros chipset so this fix won’t work for those adapters.
Big thanks to the people out there maintaining that github repository, it really helped me out big time. I also know that this isn’t exactly the most informative post but I couldn’t find any fixes for my specific adapter on Linux Mint so I figured I would post this so that anyone else with this problem can find a solution quicker.