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 credential loop in Microsoft 365 happen because of issues like a damaged Outlook profile, poor internet connection, or a corrupted OST file.

Solution 4: Disable Antivirus and Firewall Temporarily

If restarting Outlook or fixing the profile doesn’t work, converting the OST file is often the next step. EdbMails OST to PST Converter can help in these cases by recovering data from the inaccessible OST files and restoring them without data loss. Outlook sync issues can be because of corrupted Outlook OST or PST files. Therefore, now we will Repair Outlook Profile Online know the steps to repair the Outlook data file. Sometimes because of a corrupted OST file synchronization process stops functioning properly and thus leads to error.

Solution 7: Create a New Profile

After trying all the methods, is the outlook error synchronizing folder not resolved? You can try fixing it automatically with the Wondershare Repairit for Email. As PST files are bigger and so chances of the getting corrupted are high.

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 Outlook OST vs PST repair 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

In the main interface, you need to click on "Select PSF/OST file to repair" to upload the required file.

• The OST Integrity Check Tool runs only on .ost files and can be used to diagnose and repair synchronization issues.
• Moreover, it maintains the folder hierarchy and metaproperties of the data when processing Outlook data files.
• 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.
• As it is the replication of the existing information of Exchange Server mailbox, so the complete process does not cause any damage to the information.
• For more information about the maximum allowed share of server resources on Microsoft Exchange Server 2007, see A user is consuming their maximum allowed share of server.

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.



The OST Integrity Check Tool does not change your mailbox on the Exchange Server. The tool records any differences in a scan log so that you can see what differences the tool found and resolved. The scan log also identifies any situations that the tool could not resolve and that you must fix manually. There are various methods to resolve the Outlook sync issues, including manual and third-party solutions. Firstly, we will discuss a few manual methods to resolve this Outlook error and share the stepwise procedure of each method to successfully fix synchronization issues. Now, let us start with the manual processes to fix Outlook syncing errors.