Avoid Ad-hoc wireless networks

Disable automatic connection to any new networks and limit your connections to access point (infrastructure) networks only:
Click the "Start" button and navigate to the "Control Panel" and then to "Network Connections."
Right mouse-click on the "Wireless Network Connection" and choose "Properties".
Pick the "Wireless Networks" tab, then the "Advanced" button:
Make sure that the check box next to "automatically connect to non-preferred networks" is not checked.
Click on Access point (infrastructure) networks only to avoid ad hoc networks. This configuration prevents you from automatically connecting to any new networks and refuses all ad-hoc networks, which have the potential to monitor traffic that passes through them.