Do users have to create a LIVE account to play a Games for Windows — LIVE game?
No, you can play offline without ever connecting to Microsoft or creating a LIVE profile. Games for Windows — LIVE supports the creation and use of an offline “local” profile that exists only on the user’s computer. This account will let you play the single player portions of the game, but the user will not be able to play multiplayer, gain achievements, or take advantage of the other LIVE features. However, Microsoft strongly recommends that users who wish to play offline create an online account and then use that account to log in “offline.” This makes the end-user experience better, since it ensures that saved games, purchasing /downloading add-on content for the game, and keeping the account across Xbox LIVE, Games for Windows – LIVE, and Xbox LIVE on Windows Phone remains consistent.
Do you need to activate to play when using an offline account?
No, if you create and sign in with an offline account, the Games for Windows — LIVE service is not contacted and therefore no activation or Internet connection is required.