Google recently introduced a new feature, Undo Send, which permits the sender to retract a sent email; Microsoft has a similar, though somewhat limited, feature with the ability to recall or replace a sent email named Recall This Message.
Google’s Undo Send works for all emails, but it is time-constrained: Google permits up to 30 seconds after an email is sent to Undo Send; however, any email-oriented activity other than Undo will end the countdown prematurely.
The Undo option is displayed along with View this Message after every sent Gmail-based email. You must first access your Gmail account settings and enable Undo Send to make it work.
Bartie Scott of Inc. highlights Undo Send in her article How to Unsend an Email in Under 30 Seconds Flat.
Microsoft’s Recall This Message tries to stop delivery and, optionally, can replace a recalled email message. Recall This Message requires an Exchange Server and stops email messages sent, but only email sent internally within your organization. Also, the success of a recall depends on the recipient’s settings in Outlook:
- If Automatically process requests… is enabled, recall will be successful
- If disabled, the recipient will receive both the original email and the recall request; the original email is deleted only if the recipient opens the recall message first.
For more information, please view the Microsoft article Recall or replace an email message that you sent.
Given the short timeframe of Undo Send and the limitations of Recall This Message, your best option is to avoid recalling a message by:
- Double-checking the To, Copy, and BCC recipients,
- Ensuring that you have attached the desired file (if any), and
- Giving yourself enough time to cool off before sending a heated email.