Q: I really want to protect data over wireless networks. How do I stop my Windows 7 laptop users from using free Wi-Fi at places like Starbucks and the airport?
A: You're in luck. Windows 7 exposes extensive wireless configuration options through Group Policy. They're available in the policy engine in a few places. The primary location is in the Wireless Network (IEEE 802.11) Policies section in the Security Settings container. In particular, consider restricting the SSID list to authorized corporate networks.
For complete details and possible prerequisite steps to take, see the TechNet tip "Using Group Policy to Configure Wireless Network Settings."