You can open the "network sharing center" by right-clicking the wireless connection's tray icon. If there is a red x in there or yellow exclamation, click on it and Windows will attempt to troubleshoot the problem.
If that fails, you can clear out your wireless settings by uninstalling and reinstalling the drivers in Device Manager. Just right-click on the driver and choose uninstall. And then from the Action menu choose "Scan for Hardware Changes". You will need to re-setup your wireless network, because this will erase all settings and passwords.
If that fails, try resetting Winsock by doing the following:
- Click on Start button.
- Type Cmd in the Start Search text box.
- Press Ctrl-Shift-Enter keyboard shortcut to run Command Prompt as Administrator. Allow elevation request.
- Type "netsh winsock reset" without the quotes in the Command Prompt shell, and then press the Enter key.
Restart the computer.
You may also need to reset TCP/IP Internet Protocol stack.
Click on Start button.
- Type Cmd in the Start Search text box.
- Press Ctrl-Shift-Enter keyboard shortcut to run Command Prompt as Administrator. Allow elevation request.
- Type "netsh int ip reset" without the quotes in the Command Prompt shell, and then press the Enter key.
- Restart the computer.
If all that does not fix it it may be a defective wireless card