If your Autodesk product won't authorize automatically over the internet, on the form you fill out to authorize via email they'll ask you to fill in your computer's server name and MAC address. Many customers call us wanting help to find these. The more computers have become "user friendly" the less we need to know about the workings behind the scenes, so the less we learn how to work on these kinds of things...
In order to find the server name and MAC address, first you need to get to a command prompt. In Windows XP (and I'm told in Vista too) go to the Start menu and find "Run". When you click on that, you'll get a place to enter a command. Type in "CMD" (with no quotes) and hit enter. This will put you in the old DOS-looking interface. At the prompt, type in "IPCONFIG /ALL" (again without the quotes) and you will see something very like this illustration. The Server name is displayed as Host Name, and the MAC address is displayed as Physical Address.Write these down, I mean you actually have to use a pen or pencil, and paper, so you'll have them on hand when you contact Autodesk. The MAC address should be written with no dashes or spaces, by the way.
Voilà! as my French friends would say, which is a lot quicker than saying "There you have it" or "Here you go" or "That's it!". "Voilà" is one of the most useful words not in the English language.
This procedure can also be used if you want to obtain a license file before you install the Autodesk License Manager (AdLM) tools - in fact, that's where this information lives on the Autodesk website.
Another little tip - you can get to the C: prompt in Start>All Programs>Accessories if you have Windows XP.