WordPress MU

Long Day, I got XP up on wamp, now i got it up on Vista too but,.... when i try to login to dashboard it just sits there. I tried a different password, said incorrect password. Anybody out there seen this before?

What about the regular posts/pages?
Do you have your hosts file right? Check each line, maybe you are missing a domain.
Is your internet connection turned off?
I think it is logging you in and then is trying to redirect and unable to do so. Is it timing out?

NO TIMEOUT,

127.0.0.1 LOCALOHOST.LOCALDOMAIN
127.0.0.1 TEST1.DOMAIN.TLD
::1

BRAND NEW INSTALL

There really is no reason WPMU would work on XP and not on Vista. Perhaps try xammp.

And turning off caps lock, too. ::)

ok, sorry

This is mine:
127.0.0.1 localhost
::1
127.0.0.1 localhost.localdomain
127.0.0.1 domainname.com
127.0.0.1 subdomain1.domainname.com
127.0.0.1 subdomain2.domainname.com
127.0.0.1 subdomain3.domainname.com

Although you have the ones for the subdomains, you don't seem to have the following:
127.0.0.1 domainname.com
Maybe your setup is looking for the main domain, which might not exist on the internet. The subs exist on your local machine.

If hes able to reach the login screen, theres nothin wrong with the hosts file.

OP: Are you trying to login to the main domain, or are you trying it on a subdomain? If you see the login page on the main domain, then, like @MrBrian says, there is something else wrong.
You will be able to login to a subdomain even if you don't have the main domain in your hosts file- I just tried it.
Turn off your network connection, save your hosts file, re-start Apache and MySQL.