Sounds like your Wireless card is disabled, depending on your Operating system and your wireless Card type, You need to get into the Network Connections settings, and right hand click on the Icon of your wireless connection and select enable.
Also, make sure your card in not added to a Connection bridge, when you right hand click after enabling, you should see the option BRIDGE CONNECTIONS, if you don't you will have the option to REMOVE from bridge, do the Remove if you have that option.
If you are using Windows Wireless Manager, after enabling the card, right hand click on the wireless Icon near the clock bar, and select View Available networks, If using Windows management , you will see a list of available networks , choose yours to connect, if the card has it's own management software, you need to use that to configure your connection options.
Hope this helps