You might have the wrong password for your wireless connection, if you sure that you have the right password.
Best fix for this is to by pass the linksys software and just use the windows wireless connection manager.
On the bottom right of your desktop screen, where you see the time. Right click on the green icon that says "Linksys WLAN manager" and click " use windows XP configuration manager", click yes if prompt. After that, windows is now managing your wireless connection.
To connect wirelessly, go to start > control panel > network connections
- right click wireless network connection
- go to properties
- go to the wireless networks tab
- check the box that says use windows to manage your wireless networks
- click ok
- right the wireless network connection icon again
- click on view available wireless networks
- connect to your network
make sure that you have the correct password with the right cases.
Hope this helps