Why does my Outlook keep receiving duplicate messages?

There are a couple of situations which may cause Outlook to download duplicate messages:
  1. KB292249: Outlook Downloads Messages from a POP3 Server Twice
    http://support.microsoft.com/default.aspx?scid=kb;en-us;292249
  2. KB317945: Mail Retrieval Problems Occur When You Receive POP Mail
    http://support.microsoft.com/default.aspx?scid=kb;en-us;317945
  3. KB284404: Password Prompt, Duplicate Messages Appear If Outlook Profile Has Two POP3 Accounts
    http://support.microsoft.com/default.aspx?scid=kb;en-us;284404&Product=ol2002
  4. KB289942: POP3 Headers Are Duplicated
    http://support.microsoft.com/default.aspx?scid=kb;en-us;289942&Product=ol2002
  5. Using Anti-Virus Software
    Many of the anti-virus programs that scan email can cause this issue as well. When the messages are large, the software causes a 'timeout' to the server before it sends back a flag that id's the message as being read. As a result you recieve the message over and over.
How do I get it to stop?
The easiest and fastest solution to this problem is to log-in to the mail server and delete your mail message that is causing the problem - or all of them for a fresh start. (NOTE: make sure that you have downloaded your messages first just in case!) Follow these steps to delete your messages:
  1. Go to Mail.NewTechLabs.com
  2. Enter your entire EMAIL ADDRESS for your user ID and then your password
  3. Once logged in click the "main" link
  4. Once your main mailbox is opened simply click the "delete all" button
  5. If your mail is looping one message over and over then simply delete that one message!