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Sign into Outlook Web App with your Login credentials.
Click the Settings gear in the top-right corner of the screen.
Click Viewall Outlook settings at the bottom of the Settings menu.
Click Mail in left-hand menu.
Select Junk email. There will be options for blocking senders, setting safe senders, etc.
Outlook
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for Mac
Click Junk.
From here, you can click Junk or Block Sender.
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