WiFi

Hello,

I got a question on a problem with Vista Computer and WiFi.
I have three computer all connected to my Network via WiFi.
The Network is connected to Internet through ADSL modem/router.
Two of the computers are XP Pro and have no problem regarding WiFi.
The third one is a Vista Home Edition Premium SP1 and is a laptop.
The problem is whenever I boot it up the WiFi is automaticaly connected, as it is intended to do, but with limited access for local only. (even I can't see my other computers).
I have to manually disconnect it, manually reconnect to (other network)the same network, and it will be normally connected.
Although it is not a real problem but it is annoying.
Could anyone have an idea about what is the matter?
Thank you