After a long period of observation, Google Mail service had approved their new feature "Gmail Undo Send". It will add a new dimension to the traditional mail system. This feature gives you the option to take back a message you just sent.
To enable undo send gmail, follow the steps below.
2. From the General settings tab, Scroll down to "Undo Send" and check the box “Enable Undo Send” to enable. Now set the cancellation period. It is the amount of time you have to decide if you want to unsend an email and the end of the session your message will be sent.
3. Click “Save Changes” to save your settings.
Now you are eligible for Gmail Undo send.
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