Welcome to SF,
Check the browser's settings, remove or uncheck any proxy settings if found.
Any Security Software installed - McAfee, Norton or similar?
If you are using any 3rd party utility manager to wireless connect, disable the WLAN Auto Config for Vista/Win7 from Control Panel's Services. Click on Start and type services.msc
press enter, locate WLAN Auto Config and Disable. Otherwise, the WLAN Auto Config needs to be Started if you're using Windows WZC.
If it's still an issue please provide an ipconfig /all of your computer.
Click on Start => in run or search box type cmd
press enter (run as Admin). From the black screen, type the word ipconfig /all
and press enter. Right click on the black screen or Command prompt then choose Select All and Paste the results here.