Open Outlook
Go to the Sent Items folder
Open the message you want to retract
Select File
Select Info
Select Message Resend and Recall
Select Recall This Message
Choose Delete unread copies of this message or Delete unread copies and replace with a new message
Select whether to receive a confirmation for each recipient
Click OK
If prompted, edit and resend the message if replacing it
Note that recall works only in certain Microsoft Exchange or Microsoft 365 environments
Note that the message must usually be unread by the recipient for recall to work