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Feb 28 2024 07:00 AM - Feb 29 2024 10:30 AM (PST)
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Outlook is sending duplicated mails

Copper Contributor

Hello dear Microsoft Community 

I've got following problem:

With one of our clients there is an issue with Outlook/Mailing 
The mailbox is IMAP
If he sends Mails to someone they'll recieve the sent message, for like 20 times.
the only suspicous thing is, that we can see 3 duplicates of that mail in the 'sent' folder.
but regardless it was recieved alot more than 3 times, either way.

Do you have an idea ?
I already 
updatet Microsoft Windows & Microsoft Office 365
made a new profile 
checked for Add-Ins or antivirus applications
I also looked it up on our firewall
we also checked the log on the mailserver

and im looking forward to recieve some help from YOU 

4 Replies


In Outlook : File --> Account Settings --> Double Click the Account Name (highlighted yellow in the screen below) --> More Settings --> Tab Sent Items --> Choose option " Do not save copies of sent items".  Refer to the screen shot below.

This will ensure that Outlook doesn't store an additional copy of email since Gmail already doing the same. So with this you will be still having one email (IMAP) in your outlook/ gmail sent folder .





Couldn't find the exact image while trying to resolve the above issue.@Deepak335 This is what i am seeing below. Thanks 




Just check the outbox of outlook. If your mail is there delete it. While deleting just turn off your wifi or internet because if you are connected it will not allow you to delete the mail