Windows 7 stopped being able to connect to my wireless network

It could be a power issue see this link (Microsoft forum)

"If you are having a problem with your wireless connection after resuming from hibernate or sleep, or are having intermittent connectivity issues, try to adjust your Power Management profile to change your Wireless Adapter Settings to Maximum Performance. a. To do this click “Change Plan Settings” next to your Power Profile, and choose “Wireless Adapter Settings” and set it to Maximum Performance. You should do this with all of your power profiles. Additional guidance is available here: http://windows.microsoft.com/en-us/windows7/products/features/power-management "

Have a look in the properties of the wireless connection and see whether the encryption method has changed from TKIP to AES or vice versa - XP and Vista, at least, have an annoying habit of flipping this occasionally and it causes the kind of symptoms you describe.

I had a similar issue. Windows 7 wireless client stopped connecting to my wireless AP. I 'fixed' the problem by disabling/enabling the wireless adapter in Windows: "Control Panel" -> "Network and Sharing Center" -> "Change Adapter Settings". Right click on wireless adapter then "disable". Right click again and "enable".

My Windows 7 client connected successfully after this.

I experienced the same problem on my Windows 7 machine. I pressed the button to turn off wireless access. Later I turned it back on but then it would not connect. I restarted the machine and it still would not connect. I then powered it off, left it for a few minutes and powered it back on. After that it connected. Sounds like windows 7 was "being clever" and turned off something to save power. Note bot while being able to connect I was still able to connect with Vista.