If the recipient has the Outlook Inbox open, this notification may prompt them to immediately open the message you are attempting to recall. However, the Recall feature is somewhat limited due to the following reasons:
This feature can be useful if you send a message and then you discover errors in the message and want to prevent the recipient from reading it. However, this feature is not available in OWA (Outlook Web App).
Outlook allows you to cancel (recall) messages that you have sent to other Outlook users.