ProTip for ePO: Duplicate systems in the System Tree after a McAfee Agent force installation over an existing version
When you use the switch /FORCEINSTALL to force a new agent installation over an existing version of the agent, the entry for that system is duplicated in the ePolicy Orchestrator (ePO) System Tree.
This happens when a system property (for example, System Name, IP Address, MAC Address, or NetBIOS Name) is changed during the agent upgrade. Because the properties do not exactly match the existing entry in the ePO database, a new GUID is generated for the node.
For information on how to resolve this issue, see KB86879.