I have MOM successfully running on my corporate network (100% Windows 2000). I would now like to monitor a server on an untrusted domain.  I installed the Agent manually as per http://www.microsoft.com/technet/treeview/default.asp?url=/technet/prodtechnol/mom/deploy/mn-agnt.asp, setting the Agent Manager control to 'NONE'.

Everything seemed to go okay (I get a Heartbeat), but I am getting 21217 Application Event Errors every 5 minutes on the server I am trying to monitor. One thing that wasn't entirely clear in the 'ManualMC.txt' file is should the syntax be '<Domain>\<Server>', or just '<Server>'?

The full error description is as follows:

The Agent received no configuration from the Consolidator. This condition may occur if a new Agent starts up before the consolidator has updated its internal rules cache. It may also mean that the Consolidator no longer has any information about the agent, possibly because the Agent Manager has not been able to contact the agent for an extended period.

Contributed By: Nissim Ben-Maor [MVP MOM]
The 'ManualMc.txt' file should only contain the server NetBIOS name (15 characters the most).  So in your example:
'<server>' and not '<domain>\<server>'

You will get this error right after Agent installation until the Agent downloads rules from the DCAM.

You will need to add the manually installed Agents to Computer Groups and to force a SCAN (you will need to add them to the 'Include list' on each Computer Group they should belong to).

Next monitor your DCAM so see if there are any errors relating to these Agents (access denied etc.)

Then make sure you have a name resolution from both sides - DCAM and Agent:
From the Agent computer - try to ping the DCAM
From the DCAM - Try to ping the Agent.

If there is a Firewall / port filtering make sure to allow MOM port 1270 (to be secure).