Open your HYMS Email account Office 365 in your web browser.
Click the Settings Cog and select Mail under “Your App Settings”
Navigate to the Undo send configuration page.
Select the Let me cancel messages I’ve sent for option, and choose the number of seconds (maximum time to recall a message is 30 seconds).
Click Save to complete the task
After completing the steps, every time you click the Send button on a new message, you’ll notice an Undo button in the top-right corner, which you can use to cancel the message.
Once you click the button, you can edit and resend the message, or you can click the Discard button to delete the email.