Strange WLAN problem HP dv9500t

OS is Vista Home Premium 32bit.

We're camped in an RV park with two computers, a desktop running XP and the above mentioned HP laptop running Vista. both are fully up to date.

We are subscribed to a wireless network, SmartCom. It has worked perfectly all the time on the XP computer.

About 3 days ago, the HP laptop would no longer "associate" with the SmartCom WiFi. It detected it, no problem, but just wouldn't connect to it.

Because the XP computer works fine with the same network, we first assumed there was some kind of problem with the HP. Tried everything from installing the latest Intel driver (date 2/8/2008), deleting and reinstalling, you name it.

On a hunch I put the HP in the car and went a mile away to another WiFi hotspot. Voilla, instant connection.

Doing this also purged the computer of the previous SmartCom networks, of which there are several in the park (some people are running wifi off of it with their own networks).

So when I got back and tried the SmartCom again, it would have redetected them. The Vista computer still won't work.

We're going to call the WiFi provider on Monday, if anyone has any suggestions as to what we might try either with the Vista computer or what we should tell SmartCom to check, it would be GREATLY appreciated.