Did you know you can undo a sent e-mail in Gmail? It's a lesser known feature, but Google just made it even better than it was before. When it first launched, you were given a 5-second window during which you could hit "undo."
Now that's up to 30 seconds, Google Operating System discovered.
The feature is hidden from most users who don't know where to look, so here's a quick guide to avoiding social and workplace faux pas with the click of a button. Be aware that the feature is part of Gmail Labs, though. That means it's still in testing and it might not always work as intended.
Go to Gmail Labs
Scroll Down and find Undoo Send and click on Enable it and Then Click on Save Changes..
Customize Undo Send's Duration
and set it to its max. value 30Seconds...
Write and Send Your E-mail
Now that Undo Send is enabled, it works each time you send a new e-mail. You don't have to do anything unusual beforehand to make it possible to use Undo Send with that e-mail.
Click the "Undo" Button After You Send
After clicking on UNDO button this message will appear to you..
"Sending Has Been Undone"
You'll immediately be taken back to the e-mail composition page, and your e-mail will be in draft form, unsent and ready for further editing — or deletion, if writing it was ill-advised to begin with!
NOTE : To use this feautre Use Gmail In Standard Mode not in Basic mode
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