This Hotmailog.com taught how to block someone’s emails from the inbox of Hotmail (now called “Outlook”). You will need to use Outlook Web page to change these settings because they can not be changed from within Outlook Mobile applications.
Blocking by Email Address:
1: Open Outlook website. Doing so will open your inbox if you log on to Outlook.
If you are not signed in, click Sign in, enter your email address (or phone number) and your password and click Login.