Sent a nasty email to an Ex? Accidentally hit the “reply all” button? Forgot to attach something? Don’t panic, with Gmail’s ‘undo send’ feature you can recall your email without it ever reaching your recipients’ inbox.
Here’s how to do it:
1. Log into your Gmail and navigate to the 
icon located on the upper right corner of your screen, then click on the ‘Settings‘ option from the drop down menu that appears.
2.Click on the ‘Labs’ link which is close to the right side of the screen along the top.
3. Scroll all the way down, until you see an option to “Undo Send”. Make sure you enable it.
4. Hit ‘Save Changes‘ at bottom of the screen.
Now, when you send an email, an “Undo” link will appear next to the “Your message has been sent” note at the top of the screen. Hit ‘Undo’ to recall your email. Simple.
PS: Gmail gives you 10-second window to make the ‘Undo‘ call. If you think you’re going to need more time, you can adjust the time limit up to 30 seconds within the “Undo Send” options.
~Aaron
Love this tip. I never knew it was possible to stop an email and a few times I have hit the send when I didn’t mean to do that. Thank you for all the new things I have learned!
I wish I had known about this over a year or so.
I have sent many e-mail to people that I did not mean to do so.
They all forgive me for doing so!!!!
Great tip, but I didn’t see the option to change the time limit.
Under “settings” click on the general tab, the option to increase the time is in there.