This means that the authentication setup for your sync is no longer valid. This can happen for the a number reasons particularly if your sync authenticates using Delegated Permissions. To update from Azure AD Sync to Microsoft Entra Connect, see the upgrade instructions.

Top questions it leaders have about microsoft copilot (and how to answer them)

• 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.
• The system requires that users have a first name, last name and a valid email address that conforms with your domain lock if enabled.
• Comprehensive repair solutions for Office apps—both Quick Repair and Online Repair to ensure minimal downtime.
• You can do this in the Microsoft 365 Sync Wizard on the configuration page of your platform settings.
• Create your account and connect with a world of communities.
• Ive repaired the OST and changed cache mode to only cache 1 year.
• To resolve these issues you should run the steps in this article and check whether the groups in your sync's filtering preference contain users in Azure AD.

I have multiple Office 365 Sync Errors Fix users experiencing sync errors with Outlook and office365. Another which is shown below, is a user opens a new message, or replies to one, and lets it sit for a while. When they go back to the message and press send they get an error that the message has been deleted. Ive repaired the OST and changed cache mode to only cache 1 year.

I got an error message that my company has exceeded the number of objects that can be synchronized

The idea is to provide a recycle bin of users who you can delete when flush DNS and re-sync Outlook you no longer need them. You can view your inactive users on the Users page and delete them as you see fit. 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. With directory synchronization, you can continue to manage users and groups on-premises and synchronize additions, deletions, and changes to the cloud. But setup is a little complicated and it can sometimes be difficult to identify the source of problems.

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

Comprehensive repair solutions for Outlook Not Sending or Receiving Email Office apps—both Quick Repair and Online Repair to ensure minimal downtime. To identify Microsoft-side issues affecting Office 365 services. Are you facing Microsoft Office 365 not opening or continuing to crash? This is one of the most frustrating issues with Microsoft Office, often caused by update failures, corrupted files, or compatibility problems. Discover how IT leaders can address key Microsoft Copilot questions on cost, deployment, security, and integration to maximize ROI and adoption. In these cases, direct escalation to Microsoft or working with a Microsoft CSP partner, such as TrustedTech, can expedite resolution and minimize downtime.

Tools & Methods To Use to Troubleshoot Office 365 Issues

The sync will fail if the total number of all users (active or inactive) on your account exceeds the user limit placed upon it if present. The Summary sheet on the spreadsheet attachment of your sync summary includes an Updated User Count and User Limit. These figures will give you an impression of how far over the limit the account is. Sync failure alerts do not always include a full summary or attachment, you can run a test sync to obtain this data.