This article describes how to access and manage your emails blocked and safe senders lists using with the Outlook application or within Outlook.
See also Managing Blocked/Safe Senders in the Microsoft 365 Outlook webapp.Webapp for users that are using the Outlook Webapp via https://office.com
In the Outlook App while in the Home tab, Select Junk, and Junk Email Options
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When complete select Apply and OK to close the window.
If you are using the Outlook 365 Web App online sign in to https://login.microsoftonline.com/ using your SU credentials
On the right hand side select the gear icon to access settings then choose View all Outlook settings
In the settings window under Mail select Junk email.
Click Add below Blocked senders to add users to the blocked list or under Safe senders to add to the safe recipient list.
To remove and email address highlight the email to be deleted and select the trash icon to the right