It is a normal Outlook function, and these messages act as error-checking mechanisms for programs that use it for Troubleshoot Office 365 Sync and Login Issues syncing email services. In this article, we will discuss the synchronization issues in folders, and the method to solve it manually and automatically with the excellent Outlook Repair software. If these methods do not resolve the issue, we recommend that you rebuild the .ost file. To do this, delete the .ost file, and then let Outlook download the information again from Exchange Server. For more information, see the More information section of this article.

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 Outlook profile repair and recovery steps 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)

The other solution to fix fix outlook and Office 365 errors 2025 Outlook sync issues is recreating Microsoft Outlook profile. Follow each step carefully to resolve synchronization errors. Are you finding mismatches in the messages received in Microsoft Outlook in comparison to its web app?

Solution 1: Update the Outlook Application

Any problems are noted in a message that has "OST Integrity Check" as its Subject. The OST Integrity Check Tool (Scanost.exe) is installed when you install Outlook in the following locations, as appropriate for the Outlook version that you are running. 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.

• It leads to the occurrence of the issues of Outlook OST synchronization.
• We have given you complete information about the synchronization issues folders in Outlook, and the ways to solve it manually and automatically.
• You can see the synchronization status here and your new .ost file now.
• The Inbox Repair tool can be used on both .ost files and on Personal Folders (.pst) files.
• This tool also helps users fix Outlook syncing issues by repairing OST or PST files and syncing the data smoothly.
• You can try fixing it automatically with the Wondershare Repairit for Email.
• If users are facing syncing issues in Outlook due to corrupt Outlook data files, they must choose a professional tool, like Shoviv OST to PST Converter Tool.

Incorrect Outlook settings can also be one of the reasons behind Outlook synchronization errors. So, follow the below steps to reset Microsoft Outlook settings. After the files get repaired, restart the Outlook program to ensure that the Outlook syncing issues are resolved or not. You can see the synchronization status here and your new .ost file now. 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. See your Exchange Server administrator for this information or permissions.

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

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.