Hi
I have installed SP1 several times on Windows server 2003, and whenever I
do I get all sorts of RPC errors communicating with my domain controller.

Initially, I installed WS2003 and SP1, then tried adding the machine to the
domain as a member server. RPC kept saying that it wasn't working, and would
not attach the machine to the domain. Uninstall SP1 and it works perfectly.

I then tried installing SP1 after having added the server to the domain,
(again, as just a member) and after re-booting, I immediately could not see
the domain to authenticate, (logged in using cached permissions) and there
were RPC errors in the event log. Uninstalled SP1, and it works perfectly!!!

Ideas?
I seem to remeber googling and finding a hotfix that fixed this issue, but I
can't find it.

thanks

Check out this article and make sure you read the SP1 release notes.

Installing security update MS05-019 or Windows Server 2003 Service Pack 1
may cause network connectivity between clients and servers to fail:
http://support.microsoft.com/kb/898060

Microsoft Knowledge Base Article 898060 outlines a very specific and limited
situation where disruptions in network connectivity may be experienced after
the installation of either security update MS05-019 or Microsoft Windows
Server 2003 Service Pack 1 (SP1).

Specifically, the information in this article primarily applies to WAN and
LAN configurations and scenarios where routers and data-link level protocols
that have different Maximum transmission Units (MTUs) are used across the
network.  In these situations, any one or more of the following symptoms may
occur:

- Inability to connect to terminal servers or to file share access.
- Failure of domain controller replication across WAN links.
- Microsoft Exchange servers cannot connect to domain controllers.

The Knowledge Base Article mentioned above provides information about a
hotfix which is now available to address these issues.

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