Its probably lenovo's acces connnections taking over or possibly an intellipro driver depending on which wifi card you have.
Look at the windows wireless configuration.
Go to Control Panel > network connections
Highlight your wireless connection and on the left hand navigation menu, you should see advance adapter settings or something similar. Go to the wireless network tab and check the box for "let windows manage my wireless connections".
If that box is already checked make sure the wifi switches are on. There should be a physical switch on the laptop and I believe the Fn + F5 combo toggles the wifi radio on lenovos.