If you are experiencing this problem, you probably have your email account configured to use POP. The way POP works by pulling emails from the server and downloading them onto your workstation. An alternative method of configuring your email account is IMAP. IMAP views emails on the server rather than downloading a copy to your workstation. Configuring a new account using IMAP should prevent duplicate messages from being downloaded to your email client. Once you have configured the new account, you can copy over any folders from the POP account to the new IMAP account to preserve your email organization and then delete the POP account.
If you would rather keep your current POP account, or your mail server does not have IMAP capability, you may change your email client settings to delete emails from the server after downloading them. If you choose this method, it is recommended that you periodically create a backup copy of your emails. This article gives instructions for Outlook 2007, 2010, 2013, and Thunderbird:
Configure POP email account to delete messages from the server
If you would rather not delete emails from the server, or if your mail client has already downloaded the duplicate messages, you may create a filter that sends all old messages to a separate folder. This is a workaround since your mail client will still download the messages, but at least they will not flood your inbox. See instructions below:
Outlook 2010 & 2013
1. Create a new folder for the old messages
2. Click the File tab > Click Manage Rules & Alerts.
3. In the Rules and Alerts dialog box, on the Email Rules tab, click New Rule.
4. Under the "Start from a blank rule" category, select "Check messages when they arrive"
5. Select "Received in a specific date span"
6. In the Step 2 area (below rule actions), click on the blue underline text "specific date span"
7. Check the box next to "Before" and select the date cut-off you want to use.
8. Click Next, and click Next a second time to bypass the Exceptions rule options
9. Select "Move it to the specified folder"
10. In the Step 2 area, click on the blue underline text and select the folder you created earlier.
- Note: Instead of moving these type of messages you could select "mark it as read", "delete it", or "permanently delete it" (this last option would remove the message from the server as well so that Outlook couldn't attempt to download it again)
11. Click Next
12. Specify a name for this rule
13. You can check the box if you'd like to "Run rule on messages already in inbox"
14. Click Finish
Outlook 2007
1. Create a new folder for the old messages
2. Select Tools > Rules and Alerts
3. Click on New Rule
4. Under the "Start from a blank rule" category, select "Check messages when they arrive"
5. Select "Received in a specific date span"
5. In the Step 2 area (below rule actions), click on the blue underline text "specific date span"
6. Check the box next to "Before" and select the date cut-off you want to use.
7. Click Next, and click Next a second time to bypass the Exceptions rule options
8. Select "Move it to the specified folder"
9. In the Step 2 area, click on the blue underline text and select the folder you created earlier.
- Note: Instead of moving these type of messages you could select "mark it as read", "delete it", or "permanently delete it" (this last option would remove the message from the server as well so that Outlook couldn't attempt to download it again)
10. Click Next
11. Specify a name for this rule
12. You can check the box if you'd like to "Run rule on messages already in inbox"
13. Click Finish
Thunderbird
1. Create a new folder for the old messages
2. Select Tools > Message Filters
3. Click on New...
4. Type in a name for the filter
5. On the first dropdown menu of the first section, select Date
6. On the second dropdown menu, select is before
7. Enter today's date.
8. In the second dropdown section, select Move Message to
9. On the second list hover over your email, and then navigate through the folders until you reach the one you created for the old messages.
10. Click OK to save the filter.
If you already have a bunch of old emails flooding your inbox, you can use the filter to move these messages to the folder. To prevent very recent messages that you still want to access from being sent there, you could use the procedure above to create a second filter with an earlier date, perhaps a week or a month ago. To do so:
1. Access the Message Filters pop up.
2. Select the filter you want to use.
3. Select Inbox next to "Run selected filter(s) on:"
4. Click Run Now.
