With message recall, a message that you sent is retrieved from the mailboxes of the recipients who haven’t yet opened it. You can also substitute a replacement message. For example, if you forgot to include an attachment, you can try to retract the message, and then send a replacement message that has the attachment.
Message recall is available after you click Send and is available only if both you and the recipient have a Microsoft 365 or Microsoft Exchange email account in the same organization.
To recall and replace a message
In the folder pane on the left of the Outlook window, choose the Sent Items folder.
Open the message that you want to recall. You must double-click to open the message. Selecting the message so it appears in the reading pane won't allow you to recall the message.
If you have the Classic Ribbon, from the Message tab, select Actions > Recall This Message.
If you have the Simplified Ribbon, select the Message tab and then select More commands (...). Point to Actions and select Recall This Message.
4. Click Delete unread copies of this message or Delete unread copies and replace with a new message, and then click OK.
5. If you’re sending a replacement message, compose the message, and then click Send.