Hi,

My two cents, try this newsgroup as well:
microsoft.public.windows.live.messenger

PS: Cross post this to the live messenger newsgroup.

"David McGown" <dmcgown(nospam)@apriso.com> wrote in message
news:9DF2DE6F-2644-43A0-BCEC-C6421ED2DDE1@microsoft.com...[color=blue]
> I've installed Vista (Build 6000) and Windows Live Messenger (Build
> 8.0.0812) and cannot get Messenger to sign in. It gives the same error
> every time - 81000306. This is a fresh & clean Vista install and the local
> firewall is disabled but there is a firewall on our router. Since all of
> our XP SP2 users have no problem with the same version of Messenger, I am
> guessing that there is something different about the way Vista works with
> our router. My IT guy is reluctant to change anything at this stage unless
> I can make specific requests about what needs to change.
>
> Any ideas what to change that might fix this? Is this a known
> incompatibility with Vista and Messenger?
>
> Thanks.[/color]