You can also check the server status of Outlook.com for outages here. If your email is working on the computer and there is no outage, the issue might be with your email app.
Can't sync calendar and contacts after set up
Outlook Web App Sign In
If you set up your email as an IMAP or POP account, your calendars and contacts won't sync. You'll have to add them as an Exchange ActiveSync account. Also make sure that your email app has the correct permissions to access your calendar and contacts.