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Troubleshooting: 'Unknown error' when trying to delete mail in Outlook 2013
roubleshooting: 'Unknown error' when trying to delete mail in Outlook 2013
When trying to delete some mail messages, an Unknown Error message is displayed. Additionally, an issue might arise where a mailbox folder, inbox, outbox, or sent items folder is not working as expected. These problems occur when the upgrade has not completed correctly.
To rectify this, repair the Office installation.