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Occasionally Outlook Express may try to send a message repeatedly. We'll look into a couple of causes, and solutions, to sending multiple copies.

There is something strange going on with my Outlook Express version 6. When I send an Email with an attachment it's sent something like 40 times! Of course, while sending that mail I notice on my screen nothing at all about this curious fact. It seems to me - but I certainly do not know why or how - that probably my Outlook Express duplicates that mail and delivers it 40 times! I checked my configuration but I see nothing strange with that. Can you tell me what is the problem and how to solve this?

I did a little research, and I'm finding a couple of common causes.

The good news here is that either should be easy to fix.

The situation here is that your email program, Outlook Express in this case, is repeatedly sending a message over and over.

"The most common cause of repeated sends ... probably anti-malware tools that are trying to scan outgoing email ..."

There are two common causes.

Anti-malware Tools

The most common cause of repeated sends that can be traced back to your actual mail program is probably anti-malware tools that are trying to scan outgoing email, or otherwise interfere with the proper operation of the mail program. It's a common cause of repeated (or failed) downloads of email, and when the feature is enabled to scan sent mail, it can interfere there as well.

Depending on the type of interference, the email program responds by saying "well, that didn't work, I'll try to send it again" - and again, and again.

The solution here is pretty simple: locate that feature in your anti-malware or security suite, and turn it off. You may need to close and restart your email program, or even reboot your machine for the change to take effect.

Outlook Express Mailbox Limits

Outlook Express apparently has a 2 gigabyte file size limit for its mailboxes.

Normally, that doesn't affect most people, but I've definitely seen reports of it doing exactly what you've described when the Sent Items folder approaches 2 gigabytes. Smaller emails might make it out for a while, but a larger attachment might be enough to exceed that size limit, and thus cause the problem.

My recommendation is to create a new folder - call it what you will; perhaps something like "SentArchive", and move all the messages in your Sent Items folder to the Sent Archive folder. That should a) retain all your sent messages should you need to refer to them, and b) empty the Sent Items folder so that this problem doesn't happen again.

Article C3909 - November 4, 2009 « »

Leo Leo A. Notenboom has been playing with computers since he was required to take a programming class in 1976. An 18 year career as a programmer at Microsoft soon followed. After "retiring" in 2001, Leo started Ask Leo! in 2003 as a place for answers to common computer and technical questions. More about Leo.

Not what you needed?

Bosque Bill
November 10, 2009 8:45 AM

I had a friend with this problem with an older version of Outlook Express. The solution was similar to Leo's second explanation above, but very different. She had somehow accidentally checked a box in her email account preferences that would automatically break up the email into separate messages of less than x size, where x defaulted to a fairly low number. The default number being set up back in the day when most people's emails were restricted by the POTS ISP to a small size. She only had this problem when she tried to send a photo or several photos which exceeded the x size limit. Once I figured this out she unchecked the box and all was well.

Jim Huffman
November 10, 2009 2:30 PM

I've had this and similar problems with Outlook Express over the years.
I've found and fixed most errors in Outlook Express by trial, using different options in creating an email, and error, sending the email to my self.
Your self addressed email will show what you did right and what you did wrong.

Alex Netherton
November 10, 2009 2:59 PM

Switch to Thunderbird. Problem solved.

Lynn Hancock
November 10, 2009 3:03 PM

I have had this type of problem in Outlook (I don't use Outlook Express, but a similar thing could happen). It can occur when I send an email to a list of recipients.

Let's say that I am sending to a list of ten people. All goes well until it is sending to the tenth and last person. Due to a problem AT THEIR END, the email is rejected. My email program says "well, that didn't work, I'll try to send it again". Instead of just sending it again to only the tenth person, it starts over and resends to the whole list. This process continues until the email finally gets through to the tenth person or the mail process gives up (usually the latter). Thus the first nine on the list get a heap of copies of the same email, and the tenth person may not get it at all.

This can be very embarrassing when you fill up several people's inboxes with multiple copies of the same email!

November 12, 2009 1:07 PM

HA! Lynn's comment explains why sometimes I receive identical copies of the exact same email from the exact same sender only moments apart. Thank you.

January 19, 2010 12:02 AM

Second Solution worked for me, my sent items reached 2GB in size, i created a new folder named it sent archive and transfered all my sent items on the new folder, compacted the sent items and now its working OK. thank you very much...

October 7, 2010 2:47 PM

I am having a problem with Outlook, I receive my email for example it says there are 162 - they download and then it starts all over again and continues doing this until I turn it off. I have told my IP but they reckon there isn't anything to do with them??? I don't really know how to stop them from repeating the download?? It takes up to 2 hours for it to finish: Can anyone give a suggestion?? PLEASE

March 3, 2011 10:21 AM

Thanks for the information on duplicate copies of e mails.
I found e mails in the sent file that had not been dumped since Jan. 2009/
Dumped them, and it solved my problem.
Thanks again.

Varghese V George
April 28, 2012 12:59 AM

Thanks Leo for the explanations you have provided onsite. For me it must be 2Gig thing... let me check, my sent folder holds all my mails for the past 4yrs or more!

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