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Sign into Outlook Web App with your Login credentials.
Click on the Settings gear in the top-right area.
Click Mail in the lower-right area.
On the left side of the screen, click Block or allow. This is under Mail and then AccountsClick on View all Outlook settings at bottom of the new area
Click on Mail in left hand menu
Choose Junk email in next column, there will be options for blocking senders, setting safe senders, etc.
Outlook 2016 for Mac
Click Junk.
From here, you can click Junk or Block Sender.
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