Hi @Safs-3080,
It has been for a while, how is everything going now? Have you got your issue fixed yet?
In order to confirm if your issue is related to your Outlook desktop client, I would suggest you to log in to your web mail and see if you would still receive those email messages there.
If everything can work fine from your web mail side, then please follow the steps below to troubleshoot your client.
- In order to avoid possible issues, please check your "Sent Items" folder and "Outbox" folder from your Web Mail again and make sure you have deleted the problematic email messages from these folders.
- Log files in your "Sync Issues" and "Local Failures" folder in your Outlook might cause similar sync error. So, it is suggested for you to empty the "Sync Issues" and "Local Failures" folder via folder view like below, and then re-start your Outlook desktop client to see if the issue could be resolved.
- If the issue still continues, as Andy said, corrupted data file and corrupted Outlook profile can lead this issue as well, so please try creating and using a new Outlook profile via Control Panel > Mail > Show profile and see if there is any difference.
Hope this can be helpful.
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