Unable to connect to .NET service after Active Directory m..

Archived from groups: microsoft.public.windowsxp.messenger (More info?)

My company is in the process of migrating from a Windows
NT 4.0 domain to an Active Directory domain. After the
workstations are migrated, Messenger (Windows Messenger
5.0 or MSN Messenger 6.x) will no longer connect to
the .NET service. This only appears to happen on XP
workstations. If the workstation is moved back to the NT
domain, Messenger works fine. There are no configured
Group Policies in effect for Messenger and a reinstall of
Messenger will not correct the problem. We've tried
bypassing the proxy server and firewall, but the problem
remains. Has anyone seen this or have any idea how to
correct this problem?