Hi @Stecotech BV ,
Welcome to our forum.
According to your description above, I noticed that the not-loaded e-mail is not visible from your web mail, right?
If yes, I'm afraid there might be something wrong with your Outlook datafile. As I know, for IMAP email accounts, Outlook downloads and caches email messages from the mail server and keeps all the items in sync. Therefore, normally the content of Outlook local datafile should be consistent with the server side. In order to further confirm your issue, please follow the steps below and see if this issue could be resolved:
- Find the location of your datafile via Outlook>File>Account Settings>Account Settings>Datafiles>Select your email account>Open file location.
- Exit your Outlook desktop client.
- Rename your datafile to other filenames.
- Re-run your Outlook and wait for sync to end. If the issue still continues, there could be some add-ins in your Outlook client that cause this issue, so it is suggested to start your Outlook in safe mode (Press Win + R, type “outlook /safe”, press Enter.) and see if the issue continues.
Hope this can be helpful.
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