Instant regret: when you press send and realize that the email you sent had a glaring spelling mistake in the subject line. For a long time, users just had to accept their mistakes and move on — all that has changed with Outlook Web Access (OWA).
With OWA’s “Undo Send” feature, you can cancel sending an email for up to 10 seconds after pressing the send button.
Here’s how to set this feature up for your account: