Sign out of Outlook.com

The sign out link is hidden on a menu under your account name on the right. Click on your name to pop out the menu where Sign out is.

Sign out of outlook.com

Tip: if you are sharing a computer logon with another person, or just need to quickly check your account and they are logged into their account, you can use InPrivate browsing. Click on the gear icon (the one to the right of the house and star in the screenshot) the Safety to find InPrivate browsing. Or use the keyboard shortcut of Ctrl+Shift+P to open an InPrivate browser session.

If you have Firefox or Chrome installed, use a different browser to open the second account.