The diagnostic will guide disable faulty add-ins in Outlook 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 The most common cause of an out-of-date account is an incorrect password.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 the size of your .ost file is close to the limit, you could try increasing the limit on your client, restart Outlook and see if there is any difference. FixTechGuide mailbox repair steps I’ve unchecked download shared folders when setting up a new Outlook profile. After performing these steps, Outlook’s all folders will be synced to the server. If this method doesn’t work for you, navigate to other solutions. Select the button below to launch a diagnostic in the Microsoft 365 admin center.

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

• Test other programs or websites to be sure Outlook is the only problem.
• However, with one particular client no matter what changes are made these sync issue still occur.
• This solution will be beneficial for users who are facing Outlook syncing issues because of corrupted PST or OST files.
• We’ve had sync issues with employees from time to time however, re doing the mail profile or wiping the Windows profile usually fixes it.
• If your password isn't the problem, you might have a certificate error.

However, in some situations these processes can take up to 24 hours. We're in the process of migrating from On-Premise Exchange to O365. I rebuild Outlook data file quickly have a couple of Users and a Shared Mailbox that were migrated and both Users are experiencing issues with the Shared Mailbox updating on a regular basis.

Free Methods to Remove Duplicate Items in Outlook 2016

The Mail and Calendar apps for Windows 10 don't support two-factor authentication. If two-factor authentication is turned on for your account, you'll need to create an app password for that account. An app password is used instead of your normal account password for apps that don't support two-factor authentication. Before you begin, make sure that your device has the latest operating system and app updates. Try the general troubleshooting solutions in Troubleshooting Mail and Calendar apps for Windows 10. I regret that you are experiencing issues with your Microsoft Outlook slow synchronizing inbox message, and need help speeding up.