Outlook 2016: POP3 duplicates after installing the February 16 Update
After applying the February 16 2016 update for Office 365, version 16.0.6568.2025, you may encounter the following issues in Outlook 2016 when you are using a POP3 account.
When you have the POP3 account configured to leave the emails on the mail server for x days, the setting isn’t being respected and all emails are deleted from the mail server anyway.
When you have the POP3 account configured to leave all the emails on the mail server, the emails are repeatedly being downloaded and thus cause duplicates.
Microsoft is working on a fix but in the meantime, you can use one of the following workarounds.
- Configure your POP3 account not to delete it after X days but leave a copy on the mail server (in some cases, you’ll then end up getting the second issue).
- Configure your POP3 account to not keep a copy on the mail server.
- Configure your account as an IMAP account instead of a POP3 account.
- Uninstall the update by rolling back to version 16.0.6366.2068 or even earlier.
For cleanup tips see: Delete duplicates after emails got redownloaded.
Uninstalling the update
Before uninstalling the update, disable automatic update via:
File-> Office Account-> Update Options-> Disable Updates
Additionally, create a reminder in your Calendar to re-enable updates in April as a fix for this issue should be deployed by then.
To uninstall the update and revert to the February 9 build, open a Command Prompt as an Administrator and run the following command:
"C:\Program Files\Common Files\microsoft shared\ClickToRun\OfficeC2RClient.exe" /update user updatetoversion=16.0.6366.2068
If you get an error when trying to revert to this build, revert to the January 25 build instead:
"C:\Program Files\Common Files\microsoft shared\ClickToRun\OfficeC2RClient.exe" /update user updatetoversion=16.0.6366.2062
Outlook 2016 POP3 Bug Deletes And Duplicates Emails
Author: Spandas Lui 1 March 2016 7:30 AM
Microsoft’s Outlook 2016 currently has a bug that deletes emails from your inbox if they’re stored on an email server or duplicates emails in your inbox. This issue only affects Outlook 2016 configured to download emails using the POP3 standard. If you’re currently experiencing one of these problems, here’s a way to work around it while Microsoft tries to figure out a more permanent fix.
According to the Microsoft support page, the issue affects Outlook 2016 version 16.0.6568.2025 configured to use POP3 and have the Leave copy of messages on the Server setting enabled.
You may be experiencing emails being deleted on the server if you have the option Remove from server after [x] days enabled. As for duplicated messages, this can occur if you have the Remove from server after [x] days disabled.
Microsoft is still scratching its head at this one so there’s currently no patch available for the issue, but the company has provided instructions on how to work around the problem. One of these is quite simple: configure your email account with IMAP instead of POP3.
This will only work if your email server supports IMAP connections. Alternatively, you can revert back to an earlier version of Office 2016, given the bug only affects version 16.0.6568.2025.
You can find a step-by-step guy on how to work around the problem over at the Microsoft support page.