How does it happen? Two voices in your head simultaneously cry out, "Go ahead and click send, you're all set" while the other one is screaming "You forgot the attachment!" or "Hey Dumbass, you clicked Reply to All" or even worse, "Don't send it while you are still fuming! Wait!" We all know how that movie ends and we all know how we wish it could unS-END.
Can you recall, retrieve or unsend an email message that has gone out? No, the answer is the NO. In the old days of AOL and even Groupwise, you sure could (if the recipient had not opened it). But today, short of getting onto the recipients actual PC and/or smartphone and/or webmail and/or laptop and/or the other tens of places your ONE email can land, you can fuhgedaboudit.
GMail has a new feature in its Google Labs that allows you to "unsend" a message within 5 seconds and that's kinda cool - I say meh.
Now, what you CAN do if you are an Outlook user is set up your outbound messages to sit in your outbox for a few minutes before they deploy. By default, Outlook is set to send an email out of your OUTBOX and in to another's INBOX as soon as you hit the SEND button - immediately. You can turn that off and then tell Outlook how often it should send - like every 3, 4, 5 or ten minutes. Here's how you set that up:
From Outlook, begin by going to Tools > Options > Mail Set Up tab. There, you will see a check box to "Send immediately when connected". When this is checked - it does exactly what it says it will do - Send an email out for immediate delivery as long as you are connected [to the internet]. If you are not on the internet, then Outlook will send as soon as it detects that connection.
You can uncheck it and then click on the Send/Receive button just to the right of that option. That leads you into the following window:
Look for the option to "Schedule an automtic send/receive every X minutes". By default, this is set to 30 minutes. So for those of you who think your Outlook is slow or not sending and receiving in a timely manner, you can change it here. I have mine set to checking (and sending) every 5 minutes. When I need something to go out immediately, I simply push the Send/Receive button on my Outlook toolbar and off it goes. Also, when someone says "I just send it to you, you should have it by now" - I also click that Send/Receive to force a check.
So my outbound emails, will wait for a few minutes before flyingout which then gives me the chance to open the email (if needed) and edit it before I look like an idiot.
Now, these tips are really good for those of use without an Exchange server and an IT department controlling our mail options. If you find that you can't change these settings or they don't seem to comply, talk to your local IT person and see if they can help.
By the way - want to learn more about using Outlook? I'm doing some webinars on Outlook (first one in a series of three is this Friday) and a few other topics in my monthly webinar schedule. Check it out here.

