ok google your laptops model + Drivers , go to the manufacturers support and download page, download the wireless card driver again. Before you install it, go to start, right click on Computer>Properties.
In the system Settings that opens up, click on Device Manager on the top left.
Expand the "Network Adapters" tree, find the wireless card one, right click it and go to uninstall.
Once its uninstalled, run the setup software for the driver that you downloaded.