Even when it appears that Outlook should be able to send an email message, factors such as Outlook emails getting caught in the outbox make this impossible. Fortunately, you can address this problem on your own by following the troubleshooting steps mentioned below. Complete each step one at a time until your problem is fixed or you've found the solution that works best for you.
Turn off automatic updates.
Because of your automatic updates, you may not be receiving emails from Outlook. When updates are applied, Outlook may crash, halting email sending and receiving.
To prevent automatic updates, go to File > Options > Advanced. Under the Automatic Updates section, uncheck the option next to Check for updates.
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