[Updated 15/01/15] If you have Windows 8 (or a Windows phone) and you want to use Windows to its full capacity including getting apps from the Windows Store you’re going to need a free “Microsoft account”, basically this just equates to a hotmail.com or outlook.com email address, note that you don’t need to use this as your primary email (or use it at all beyond just getting access to the store and logging on to your PC).

Logging on to Windows in versions 8 and later now utilizes a "cloud" based logon name for example This email address is being protected from spambots. You need JavaScript enabled to view it. to tie all the accounts and services to you as the user and also gives you the ability to log on to multiple computers or devices. You can, if you chose, still use a traditional "local account" and in fact I always recommend another local administrator account so that your always covered if you can't logon via your normal account. However if for some reason you chose to set yourself up to use a "local" account initially it will pretty soon convert to a Microsoft account anyway (or at least try) as soon as you connect to various services. That can be pretty confusing so its best to start out the right way from the beginning, so setup your Microsoft account first before you even turn-on your new PC, tablet or phone.

Just a note if you logon in a business setting either via a domain or even peer to peer things are little different. In a domain you logon as the domain user and can then optionally "connect" the Microsoft account to the domain logon, peer to peer needs a bit more planning.

A Microsoft account is basically an email address and password. The good news is you probably already have one. If you use Microsoft services like hotmail.com outlook.com, Xbox, or SkyDrive/OneDrive, the email address and password you already use is your Microsoft account. You don't have to do anything else to get one. Just use that Microsoft account to sign in to your Windows 8 PC, tablet or phone, and you'll get free online storage, apps in the Windows Store, access to Xbox music* (on windows 8). You can also use your Microsoft account to synchronize your photos, documents and files to and from One drive to whatever devices you sign in from, on your phone, laptop, and tablet.

Here is the link to signup if you don't have one already:

https://signup.live.com/signup.aspx

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