Or do you receive an error message while synchronizing your offline folder? All these scenarios indicate problems with the synchronization folder or corrupted .ost file. These syncing problems usually repair PST file without data loss happen because of issues like a damaged Outlook profile, poor internet connection, or a corrupted OST file.

Solution 4: Disable Antivirus and Firewall Temporarily

This blog talks about the causes behind Outlook synchronization errors and a few solutions to fix Outlook sync issues. We have shared five manual methods in this blog to resolve the Outlook syncing errors. Office 365 sync problems and login fixes Apart from this, we also discuss the Shoviv OST to PST Converter Tool, a professional way to repair, recover, and convert Outlook data files. This solution will be beneficial for users who are facing Outlook syncing issues because of corrupted PST or OST files.

Solution 7: Create a New Profile

While synchronizing your Outlook with the Exchange server, sometimes you receive error messages. It leads to the occurrence of the issues of Outlook OST synchronization. In such scenarios, you need to check the proper working of the synchronization process. After rebuilding the Outlook data file (OST), you must check for any missing mailbox items. After the conversion, you can import the PST into your newly created Outlook account via the Import Export wizard. The software can also directly export the OST file data to an existing Outlook profile, live Exchange Server, or Microsoft 365.

Solution 8: Rebuild Outlook Data File (OST)

After you make this change, none of the shared folders in the secondary mailbox will be available to you in Outlook when you're working offline. However, all folders in the primary mailbox will still be available to you when you're working offline. Conflicts with antivirus fix MFA prompts not working software or firewall can impact Outlook's synchronization process. You can temporarily turn off your antivirus software and firewall.

Solution 1: Update the Outlook Application

If you are still facing this issue, kindly follow the solutions below to fix the sync issues in Outlook. If you have problems when you try to open your .ost file, you can use the Inbox Repair tool (Scanpst.exe) to diagnose and repair errors in your .ost file. The Inbox Repair tool can be used on both .ost files and on Personal Folders (.pst) files. The Inbox Repair tool scans the .ost or .pst file and makes sure that the file structure is intact. The tool also tries to repair the internal data structures, if it is necessary. The tool does not interact with your mailbox on the Exchange Server.

• As PST files are bigger and so chances of the getting corrupted are high.
• All these scenarios indicate problems with the synchronization folder or corrupted .ost file.
• Each of these registered folders counts toward the objtFolder type limit on the server that's running Exchange Server.
• After these instructions, ensure the sync settings are correct and check everything is working well.
• After the conversion, you can import the PST into your newly created Outlook account via the Import Export wizard.

If you see any mismatch in the data, then the methods discussed in this guide will surely help you resolve the issue. When you add other mailboxes to your Outlook profile and enable caching of the shared mailbox folders, Outlook individually registers every folder in each cached mailbox. Each of these registered folders counts toward the objtFolder type limit on the server that's running Exchange Server. Items and logs not synced to your email by Microsoft Outlook are present in the synchronization issues folders.



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. If disabling the software resolves the issue, then change your antivirus and firewall settings and add Outlook as an exception. Use the OST Integrity Check Tool (Scanost.exe) to check your .ost file for inconsistencies.