Your Outlook.com email address is your Microsoft account. This account gives you access to many Microsoft services such as Outlook.com, OneDrive, Office Online, Skype, Xbox Live, and more. Microsoft monitors the security of your account. If there is unusual activity, Microsoft may send you a notification email. Please follow these steps to check the access history on your account:
1. Login in to your account at https://account.microsoft.com .
2. Click on the tab Security & privacy.
3. Confirm your account security settings.
4. Review the Recent activity. If there is any suspicious activity, you can flag the actions for further investigation by Microsoft.
5. Consider changing your password.
For more information, go to https://www.microsoft.com/en-us/Account/Security/recentactivity.aspx .