If it didn’t, a few targeted checks usually restore access—no need to keep resetting your password over and over. The other solution to fix Outlook sync issues is recreating Microsoft Outlook profile. We start by checking that Azure AD Connect is running and password sync is enabled. If it’s in Staging Mode or a recent change didn’t trigger a full sync, passwords won’t update in Microsoft 365.

• You'll also receive a mail (to the alternate email and to your admin email) from Microsoft 365 that indicates your tenant has encountered directory synchronization errors.
• Here’s a step-by-step approach to help you spot the issue, fix it, and avoid these sync delays down the road.
• We keep password synchronization reliable by staying proactive and making sure users know how their actions affect access across Microsoft 365 and their devices.
• This software allows users to process numerous OST files at once without any size limitations.
• Windows, Outlook, and mobile apps often save passwords so users don’t have to keep typing them.
• When they go back to the message and press send they get an error that the message has been deleted.
• If you're looking for smarter ways to manage, secure, or optimize your Microsoft 365 (M365) environment, our U.S.-based team is here to help.
• Once you have completed the steps to fix Outlook sync errors, kindly check if the error has been fixed or not.
• The Summary sheet on the spreadsheet attachment of your sync summary includes an Updated User Count and User Limit.

Troubleshooting Microsoft 365 sync issues

Similarly you should review the Users Deactivated sheet on the sync summary spreadsheet attachment as you can also delete these users to bring your total down. You'll also receive a mail (to the alternate email and to your admin email) from Microsoft 365 that indicates your tenant has encountered directory synchronization errors. For details see Identify directory synchronization errors in Microsoft 365. We also check the synchronization scheduler to confirm delta and full sync cycles finish successfully. We check that Microsoft Entra Connect (Azure AD Connect) runs the latest version and password sync is on.

Common Reasons Behind Outlook Sync Issues

If the old password still works, the reset probably hasn’t synced. To resolve these issues you should run the steps in this article and check FixTechGuide Office 365 troubleshooting whether the groups in your sync's filtering preference contain users in Azure AD. The simplest way to resolve authentication issues is to rerun the authentication process by clicking the Sign in with Microsoft on the Microsoft 365 settings page.

Address

Now, we will verify the server settings to fix the Outlook synchronization error. Once you have completed the steps to fix Outlook sync errors, kindly check if the error has been fixed or not. The M365 sync establishes a synced dataset based on your M365 data and the filtering configuration of your sync.

Get Expert Help from TrustedTech

If you're looking for smarter ways to manage, secure, or optimize your Microsoft 365 (M365) environment, our U.S.-based team is here to help. In these cases, direct escalation to Microsoft or working with a Microsoft CSP partner, such as TrustedTech, can expedite resolution and minimize downtime. Our licensing engineers can help triage complex problems and ensure you're on the right support path. Microsoft offers several built-in tools to help identify and resolve persistent issues. A vast community of Microsoft Office365 users that are working together to support the product and others. TrustedTech is dedicated to being a reliable resource for all software and technology support needs.

What should I do if my sync failed due to authentication issues?

You can stop any accounts from being brought over by adding them to the sync deny list. Please allow me a few minutes to review your question credential loop in Microsoft 365 to ensure that I don't miss anything. TrustedTech is a Microsoft solutions Partner in the following areas.

Troubleshooting Co-Authoring and Collaboration Errors

On the sync server, we open the Synchronization Service Manager and check that the last sync finished without errors. Azure AD Connect handles password sync, but it runs on a schedule—usually every 30 minutes. So, if you just changed your password, there might be a short window where your old password still works and the new one hasn’t reached every system.

To get the sync working you will either need to delete users or have the user limit on your account increased. Find out what to do if you are having issues with syncing users or groups from Microsoft 365. Real-time collaboration is at the core of Microsoft 365; however, issues can arise due to permissions, software version conflicts, or connectivity problems. There can be several reasons for the Outlook synchronization error. Before we know the solutions, we will understand a few common causes of the Outlook sync problem.



Before finding solutions, we suggest that users check their internet connection. Sometimes, Outlook sync issues can arise because of poor internet connection. If you are still facing this issue, kindly follow the solutions below to fix the sync issues in Outlook.

We check that the Work or School Account in Windows Settings is active and linked to the right domain. The sync will fail if the groups you selected to load users from no longer exist in Azure AD. Typically this is because the selected groups have been deleted from Azure Outlook Stuck on Synchronizing Folders AD since the M365 sync was configured on your account.