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Does anyone know why my office 365 email does not receive emails, but when I create a pop3 account for the same email address/account all emails download
Have you tried to configure your account with exchange on a new Outlook profile or in other Outlook desktop client for testing?
If this issue occurs only on your Outlook desktop client, it may be related to your client itself, so what's the version of your outlook client(File>Office account>About Outlook), please first ensure that you have updated to the latest version of Outlook client.
And if you were all testing on a outlook profile , in order to avoid the reason for filtering in the view settings, it's suggested to first reset your view setting to check(view>Reset view).
Also, as I know, the issue may occur when our data file is corrupted, please try to rename your outlook data file and restart your Outlook to test if the issue has any difference(File>Account settings>Account settings>Data file>open file location>rename it)
If that's invalid, the issue may also be caused by a corrupted Outlook profile, it's suggested to create a new profile and readd your account to check if it could work normally there(Control Panel>Show profiles>Add>readd your account).
If your issue still exists there, for Microsoft 365 users, we actually supply SaRA tools to figure out what's wrong and offers the best solution for the identified problem in your client, please kindly check your client by it for testing.
Hope your issue would be resolved soon.
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