If you take a look inside your EverQuest II folder you'll find another folder called TestServer.
This folder should have a TestServerHelp.txt file in it that will explain how to get the test server up and running.
Test server requires a duplicate of all your EQ2 files, so you'll need enough space on your hard drive. This is due to the test server getting updates early and these updates can't interfere with your files from the other live servers.
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