Using a Toshiba Laptop with a standard BT HomeHub and Windows Vista Basic.

My wife has had this laptop for about 5 months, and we've not had a problem
connecting to our wireless internet before. Then, in the last couple of days
it is refusing to connect to the hub. I tried pinging the hub and got error
1231 returned.

Using the built in Atheros AR5005G Wireless Network Adaptor

Anybody have any ideas?