You don't have to sign in with a Windows Live ID to use Windows Live Mail, and you can add accounts and send and receive email without signing in. However, signing in to Mail lets you connect to other Windows Live services and also lets you use Mail features such as:

• Photo email: If you create a photo email, your high-resolution photos are saved to Windows Live SkyDrive using the Windows Live ID that you sign in with. Thumbnail photos are displayed in the message, which let your recipients see some or all of the photos before viewing the high-resolution photos online. This means that you can send more than a few photos in a message, and your recipients can see the photos online in a slide show and download them if they want to.

• Messenger: If you have Windows Live Messenger installed on your computer, you can use Mail to see when a Messenger contact is available to start an instant messaging conversation.

• Contact list: If you're signed in to Mail with a Windows Live ID, you'll see the same contacts as you do in other Windows Live services such as Windows Live Hotmail and Messenger. Any changes that you make to your contacts in Mail also happen in the other services. You can share your contact information on your Windows Live Profile page, and you can ask to receive automatic updates when your friends change their contact information.

  

  Note

  If you've never signed in to Mail with your Windows Live ID, your contact list only contains the people that you've added to Mail directly.

• Calendars: If you don't sign in, you can access your calendars only from the computers that you created them on. By signing in, your Windows Live Calendar is automatically imported into Mail, and any calendars that you've created in Mail are added to Calendar.

Warning

Anyone you share a Windows user account with will be able to see your Mail accounts whether or not you're signed in with your Windows Live ID. To prevent other people from accessing your Mail account, don’t share your Windows user account with other people.