I've been struggling with the same problem for a couple weeks. First uninstalled drivers and pci wifi card, disabled firewalls, remove antivirus and nothing seemed to work. Most of the answers you'll find on the web refer to reinstalling drivers, renew ip address and so on. I did all of that. Then, a couple hours ago I realized that one of my services (VPN) had installed several services into the network config.
- Right click on the wireless signal icon in the notification area, open Network and Sharing Center,
- Change adapter settings,
- Click on the wireless adapter you're having trouble with ----> Properties,
- There I found the protocols my VPN server added without permission: Winpkfilter Lightweight Filter and ANOD Network Security Filter Driver... uncheck both of them.
That's it, problem solved (for me).
Hope this helps you too!