There is a separate program called BIM Server Manager. It is in the install DVD. It is for specifically this purpose.
You don't need it if you are logged into the BIM Server's computer. In that case it is assumed that if you have a User login on that computer, you are allowed to manage the BIM Server as well.
You can also use it to manage BIM Servers on other computers. I think it is pretty straightforward: you just log into the BIM Server with the user name and password I believe. I don't know if it is possible over the internet, I don't remember and I never tried, but I tend to believe it is possible.
I would look for more info in ACWiki and the Help.
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