The diagnostic will guide work offline mode stuck you to resolve various error conditions that can cause mailboxes to not be created. The most common cause of an out-of-date account is an incorrect password. In the notification bar at the top of the app, select Fix account.

Turn off Windows Defender Security Center

If there's a feature you think is missing from the Mail and FixTechGuide support for Office 365 Calendar apps, or if a feature in isn't working properly, you canprovide feedback directly to the Mail and Calendar team. Two-factor authentication helps protect your account by making it more difficult for someone else to sign in. It verifies your identity using your password and a contact method (also known as security info). If you would like to ask me another question in the future or follow up on your current question, you can add me as a favorite Expert.

Check if two-factor authentication is turned on for your account

Upgrade to Microsoft Edge to take advantage of the latest features, security updates, and technical support. These are the only two I've seen have this issue and I was wondering if you've seen this and figured out a 'fix'? Tempted to create a Test Shared Mailbox, but thinking that wouldn't be an accurate test for inbound mail, etc. or just actually tested by the Users at all.

Check Antivirus and Firewall Settings

• I’ve tried the Microsoft office uninstall tool provided by Microsoft (which deletes more items then just control panel uninstall).
• It is possible for a corrupted Outlook profile to impede synchronization.
• Incorrect Outlook settings can also be one of the reasons behind Outlook synchronization errors.
• I’m at wits end and Microsoft stopped helping me because they feel the problem is on our end.
• It verifies your identity using your password and a contact method (also known as security info).
• Here, we will discuss the five manual methods to fix sync issues in Outlook or OWA.
• To fix the issue, please try each of the following solutions in order.
• If you still can't sync your email after removing your account and adding it again, you might need to add the account using advanced setup.

If you can sync your email when the firewall is turned off, you'll need to allow the fix Outlook after Windows update issues Mail and Calendar apps through the firewall. Windows Defender Security Center is free security software that's included with Windows 10. If you haven't installed alternative security software, you should temporarily turn off Windows Defender Security Center.

Free Methods to Remove Duplicate Items in Outlook 2016

If you're using an Exchange account that requires advanced settings, you'll need to remove the account and add it again using advanced settings. To add the account using advanced settings, see Add an account using advanced setup. Knowing the reasons behind the Outlook sync issues will help us to fix this problem and prevent issues in communication and workflow. If you still can't sync your email after removing your account and adding it again, you might need to add the account using advanced setup. If I check the sync log I see a lot of sync errors for Inbox, sent items and a few other folders.