"Microsoft accounts are now used for OneDrive file storage, Outlook.com emails, Skype conversations, and even signing into Windows 8. You’ll want to get that Microsoft account back if it’s ever hacked — and Microsoft provides several ways to recover your account.
Check If Your Account Is Compromised
If you can’t log into your account with your normal password, it’s possible the attacker has compromised the account and changed your password. This is the obvious type of hack — you just won’t be able to access your account anymore..."Useful article. I think I posted a previous article about what to do if your Facebook account is hacked.