Outlook Sending Multiple Copies of Email

MS OutlookI received a message recently from a client that one of their friends was sending the same email message over and over again. After a bit of investigation it turned out exactly as I thought – the friend is using Microsoft Outlook. Over the years I have seen many instances of Microsoft Outlook repeatedly sending out multiple copies of the same email. There are a number of different things that can cause this, but luckily they are all fairly easy to fix.

1) The most common cause of this problem is that there are too many items in the “Sent” folder. It sounds odd, but Microsoft Outlook can only handle a limited number of items in the Sent folder. If the program reaches its limit it cannot move files from the Outbox to Sent. When that happens it will continually resend any email that remains in the Outbox folder. The fix is simple: every once in a while you need to go in and clean out those old sent emails. If you really need to have a record of the emails you sent two years ago, archive them off to an external file so you still have them, but get them out of Sent. While you are at it, also remember to empty the trash.

2) If somehow there are multiple copies of Outlook running. Do you see more than one copy of Outlook in your task manager? If so, try closing all of them and then only opening one. Or, just restart your machine. If you are consistently having the multiple send problem though, this is unlikely to be the cause.

3) If the send/receive interval is very short, like one minute, and you are sending a very large file that takes over that interval to send then Outlook may start sending the email a second time. In this case the fix is to increase the send / receive interval. Note that this is usually only encountered when sending extremely large attachments like photos.

4) Rarely, but it can happen, the installed anti-virus software will scan outgoing messages and corrupt the queue thereby causing multiple copies to be sent. The solution here is to tell the anti-virus software not to scan outgoing messages. This can happen to all email programs, such as Outlook Express, so watch for it.

I hope this helps if you are having the Outlook multiple sending receiving email problem. If it does, or even if it doesn’t, I would love to hear from you with your experience.