I have a Dell Inspiron 9400 running windows vista business 32 bit that
was hanging on the welcome screen during boot up! I went to dell and put
in the ID Tag # for my unit then downloaded the newest WLAN driver and
installed it. This has fixed the problem. I did not nor could I have
guessed that this was the cause. After reading about it in these and
other forums, all pointed me to the download and it worked.