Access denied on remote registry access, from Win2003 sp1

Hi ....

Your help would be greatly appreciated.

Having developed a native C win32 system, that runs as a service, as LocalSystem account on a Windows 2003 server.

This service is accessing data (RegConnectRegistry() - read and writes) on remote client?s (NT4 sp6a, W2K sp4 XP sp2 and W2003)

registry (HKLM\Software aso.), connecting as a domain administrator.  No problem ? every thing is ok.

But after updating the Windows 2003 server (the server with the service) to service pack 1,

My service gets ?access denied' when trying to access remote registry on all Windows 2000 professional client?s,

but no problems on nt4, xp and w2003.

This problem can be replicated with help of native tools, like this:

1. Use cmsasuser.exe on a windows 2003 server (can be found on the Internet), start it like this: cmdasuser localsystem, this will launch a command box in the security context of the localsystem.
2. In this cmd box connect to at client computer like this: net use * \\client\c$ /u:domainadmin password
3. Start (in same cmd box) regedit.exe and connect to the client?s registry.
4. Try this procedure with and without sp1 and against nt4, w2k, xp and w2003 computers.

Is this a bug in w2003 sp1 or ???

Regards

Jan

Denmark