Sign in with the account you use for SkyDrive, Xbox LIVE, Outlook.com, or other Microsoft services.
Sign in with the account provided by your work or school to use with Office 365 or other Microsoft services.
Office 365 comes with service health and troubleshooting tools for users and admins.
If you can’t sign in to the Office 365 portal (https://login.microsoftonline.com), you may be able to sign in to the individual services directly. Bookmark any of these URLs in your web browser for quick access to the services you use most frequently.