Thanks for your post!
You can find all of the TeamViewer manuals that will cover all features available with the software below.
To answer your specific question, the "identifier" when using the additional unattended access passwords is used to designate a name for the person you are creating the additional password.
Ex. You have your computer set up for unattended access with your own personal password. Bob, your tech support guy also needs unattanded access to your computer. So when you are creating the additional unattended password, the "identifier" will be Bob so that you know Bob now has access to your computer using a different unattended access password that you have created for him.
Hope this is helpful.
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