Go in "System tree", select new systems, select "Import systems from a text file into the current group (My Organization), but do not push agents "
then you can push the agent once they are in the system tree.
You could also use ADsync to import and push the systems
In short, you can follow Andre's response above. If you have Active Directory in your environment, depending on your AD structure, you may or may not want to import AD structure. Import systems only. Then within ePO you can build your own Tree. If systems in AD are nicely organized, you can just import the tree.
For a detailed tutorial, please check this video: How to Deploy and Manage McAfee Agent
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