Why doesn't WIFI work?

[WPCentral Question]

I have a Nokia Lumia 925 on T-Mobile. It is running the newest version of WP 8.1 Dev Preview. For more than a month, WIFI was working flawlessly. Now, for some unknown reason the phone connects to WIFI but will not load IE or anything pertaining to the internet. I've already restored the phone, hard and soft resetter it, and restarted it. I have a mac, so I don't think I can use Nokia Recovery Tool. I want to sell this phone so this really needs to be fixed! Thanks in advance!

 

[dameon_03]

Have you tried rebooting the router