I have used my Acer laptop for three years running on Vista. I think I have done something I shouldn't have to my laptop.
When I go to the list of wireless networks to connect to, our home network reads "The settings saved on this computer for the network do not match the requirements of the network" and instead of the signal power bar there is a red cross???
I live with three other people who can connect no problem with laptops and phones. I vaguely remember changing some sort of setting?