How to Stop Microsoft Outlook From Receiving Duplicate Emailsby Mike Benson
Receiving duplicate copies of an email message is a rather common problem that can occur while using a POP3 email client like Outlook. Beyond incorrect rule settings, there are multiple possible reasons why this can occur. The Microsoft Outlook executable is not limited to only one running instance. If multiple instances are running, duplicate requests to your POP3 server may result in downloading the same message twice. In other cases, leaving a copy of the message on the server or having two POP3 accounts for the same profile may cause you to receive the same message more than once.
Ensure Only One Instance is Running
Right-click the taskbar and click "Start Task Manager."
Click the "Processes" tab.
Click the "Image Name" column. This sorts all processes alphabetically. You should only have one "Outlook.exe" listed. If you have more than one listed, you may receive duplicate emails.
Right-click one of the "Outlook.exe" listings and click "End Task." Click "Yes" on the confirmation dialog.
Avoid Leaving Copies of Messages on Server
Click "Tools" and click "Email Accounts."
Click "View or Change Existing Email Accounts" and click the "Next" button.
Select your email account from the list and click "Change."
Click the "More Settings" button and then click the "Advanced" tab.
Click to remove the check in the box next to "Leave a copy of messages on the server" and click the "OK" button.
Profiles with Two POP3 Accounts
Open the "Tools" menu.
Click "Send/Receive Settings" and click "Define Send/Receive Groups."
Double-click the group to display the accounts.
Click one of the two accounts and remove the check from the box next to "Receive mail items."
- email @ image by Witold Krasowski from Fotolia.com