A MED-V workspace which is configured to use Network Address Translation (NAT) networking mode is not listed as a machine in System Center Configuration Manager 2007.
You may also see the following event written to the MED-V event log:
Event Type: Information
Event Source: MEDV
Event Category: Guest Agent
Event ID: 16006
Description:The Configuration Manager agent returned error: 0x80040154
You may also see the following event written to the MED-V event log:
Event Type: Information
Event Source: MEDV
Event Category: Guest Agent
Event ID: 16006
Description:The Configuration Manager agent returned error: 0x80040154