How to Undo an Email After years of testing, "Undo Send" became an opt-in Gmail feature in 2015; it's now turned on by default and can't be deactivated. Even if it's built-in, you'll still need to ...

An curved arrow pointing right. If you're a regular Gmail user, you can prevent yourself from accidentally sending the wrong email to your entire office in just a couple of clicks. Here's how.

By default, you only have 10 seconds to hit this button to unsend your recently sent email, or else it will irretrievably send and you won't be able to get it back. If you hit Undo Send ...