Undo Email Sending in Gmail
Sometimes, while writing an email, you accidentally click on the send button, and unintentionally that incomplete email gets delivered to the recipient. Such incidents are really embarrassing. Now, to avoid such incidents in Gmail, you can use Gmail lab. Gmail Lab offers the users with a great feature, with which they can undo an email sending just within 5 seconds, after the send button is clicked.
Probably Gmail takes nearly 2-3 seconds for processing an email when you hit on send button. Just after this time, an undo link is provided, which offers you the option to undo sending of that email. You can undo the sending 5 seconds without including the process time of 2-3 seconds.
When the time limit of 5 seconds reaches, the undo link automatically disappears. Consequently, you will not be able to carry any undo action for the email after that, and it will be delivered to the recipient(s).
On the other hand, this 5 seconds recall time cannot be configured according to user preferences, because it has been hardcoded in logic and the buffer cannot be changed to get more time additionally. For activating such a helpful feature, login to your gmail account and go to Setting then navigate to Labs. In Labs, try to find “Undo Send” option.