This is something I put together from posts in this forum.
I found a thread in Symantec's forum on making an unmanaged agent managed.
First, find sylink.xml in the following directory: E:\Program Files\Symantec\Symantec Endpoint Protection manager\data\outbox\agent\ There are several random character folders that hold the client builds, each folder having its own sylink.xml. I picked one at random figuring I can control the group membership once things link up.
On the client you need to run a command prompt
Change directory to the client install directory. The directory Symantec mentioned was: C:\Program Files\Symantec\Symantec Endpoint Protection My client is installed at: c:\Program Files\Symantec Antivirus due to being an upgrade from an older version.
From the command prompt run the following commands
Smc -stop
Over write the symlink.xml in the client directory with the one from the server.
Now run this command
Smc -import symlink.xml
Smc -start
The client should now be registered with the server.
Open the client and Choose Help and Support / Troubleshooting.
You can now see what group your client is assigned to.
My client was assigned to the Temporary Group. I then moved it with the consol to the IT Test Group. Clicking on Update or Update Policy makes the client pull down new settings from the server.