I have already tried that and it still says it is unknown. Here's where I got the driver from, also I've downloaded all and installed all and still no luck.
http://gd.panam.acer.com/home/
Notebook\Aspire\4720Z
Selected the right OS-Windows Vista Home Premium X32
Downloaded All WLAN drivers
"Atheros"
"Broadcom" which I know that's the one but Driver still doesn't work -.-"
"Intel"
NO LUCK :\