Outlook’s ability to connect to the mail server may be blocked by firewalls or antivirus software. After you’re satisfied, turn off your firewall or antivirus program for a while. If it does, Troubleshoot Office 365 Sync and Login Issues you might need to include Outlook exceptions in the settings of your security program. The sync will fail if the groups you selected to load users from no longer exist in Azure AD.

Methods to fix Microsoft Outlook syncing error

• Therefore, now we will know the steps to repair the Outlook data file.
• It also provides the option to export the Outlook OST file into Office 365 and Live Exchange mailboxes.
• But setup is a little complicated and it can sometimes be difficult to identify the source of problems.
• 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.
• You will need to have the correct privileges set on your Azure account in order to set up the M365 sync.
• If you don't wish an inactive user to be made active by the M365 sync, you can add the user's email address to the sync forbid list.

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. I have multiple 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. The M365 sync establishes a synced dataset based on your M365 data and the filtering configuration of your sync.

Common Causes of Sync Issues in Outlook

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. There are various methods to resolve the Outlook sync issues, including manual and third-party solutions. Now, let us start with the manual processes to fix Outlook syncing errors.

[Answered] Secured OST to PST Converter for OST to PST Conversion

So, follow the below steps to reset Microsoft Outlook settings. The sync does not delete users but rather sets them to inactive. The idea is to provide a recycle bin of users who you can delete when you no longer need them. You can view your inactive users on Microsoft Outlook Email Repair Tool Online the Users page and delete them as you see fit.

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

But setup is a little complicated and it can sometimes be difficult to identify the source of problems. We have resources to help you identify potential issues and fix them. The Support and Recovery Assistant, a tool provided by Microsoft, can identify and resolve common Outlook problems. It is capable of automatically identifying problems with account setups, sync, and inbox repair tool alternative other typical mistakes.





You can do this in the Microsoft 365 Sync Wizard on the configuration page of your platform settings. 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. Knowing the reasons behind the Outlook sync issues will help us to fix this problem and prevent issues in communication and workflow. Both of our authentication methods can fail if the Enterprise Applications entry for the sync in Azure AD is deleted or if it has had its permissions modified.

What privileges do I need to authorise the M365 sync?

It is possible for a corrupted Outlook profile to impede synchronization. After these instructions, ensure the sync settings are correct and check everything is working well. This means that the authentication setup for your sync is no longer valid.



The sync will fail if it can't find any users that comply with your filtering preferences or the system's requirements for user records. The system requires that users have a first name, last name and a valid email address that conforms with your domain lock if enabled. The most common reason for missing users is that you've run a Test Sync, instead of a Manual Sync. If that doesn't resolve your missing users issue, please follow our guide to troubleshooting missing users below. With directory synchronization, you can continue to manage users and groups on-premises and synchronize additions, deletions, and changes to the cloud.