Therefore, now we will know the steps to repair the Outlook data file. Here, we will discuss the five manual methods to fix sync issues in Outlook or OWA. 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.

Methods to fix Microsoft Outlook syncing error

It scans your local copy of the .ost file and your mailbox on an Exchange Server. The tool compares items and folders in the file and in your mailbox and tries to reconcile synchronization differences between the files and the mailbox. The OST Integrity Check Tool does not change your mailbox on the Exchange Server.

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• For persistent problems, rebuild your Outlook profile or use FixTechGuide’s free diagnostic tools to automate detection of authentication and IMAP errors in seconds.
• Users can also convert OST files into various file formats, including PST, HTML, EML, MSG, vCard, etc.
• This solution will be beneficial for users who are facing Outlook syncing issues because of corrupted PST or OST files.
• Once you have completed the steps to fix Outlook sync errors, kindly check if the error has been fixed or not.
• Now, we will verify the server settings to fix the Outlook synchronization error.
• There can be several reasons for the Outlook synchronization error.
• Knowing the reasons behind the Outlook sync issues will help us to fix this problem and prevent issues in communication and workflow.

Users can also try its free demo version in their system and process the first 50 items from each folder freely. Outlook and Office 365 sync issues can be frustrating but are almost always fixable. Start with basic network checks, enable Cached Exchange Mode, and repair your data files if needed. For persistent problems, rebuild your Outlook profile or use FixTechGuide’s free diagnostic tools to automate detection of authentication and IMAP errors in seconds. The OST Integrity Check Tool runs only on .ost files and can be used to diagnose and repair synchronization issues.

Step 4: Repair the Outlook OST File

If you have a slow internet connection or large mailboxes, default timeouts may be too short. Faulty add-ins (especially antivirus or CRM extensions) can freeze Outlook during synchronization. For a similar error caused by Outlook Stuck on Synchronizing Folders a different issue, refer to Outlook shows Disconnected in status bar if the last character in legacyExchangeDN is a space. This mode is ideal for slow connections or intermittent server responses. If Outlook syncs fine now, re-enable add-ins one by one to find the culprit.

Step 10 – Rebuild Offline Cache (OST)

Outlook lets you Outlook Login Issues Troubleshooting manually control which folders sync with the server. If the test message sends successfully but folders don’t sync, move to the next step. Upgrade to Microsoft Edge to take advantage of the latest features, security updates, and technical support.



Before we know the solutions, we will understand a few common causes of the Outlook sync problem. Re-adding the account forces Outlook to rebuild all folders and clear old guide to Office 365 sign-in errors stuck subscriptions. To view the scan log, start Outlook, and then open the Deleted Items folder. Any problems are noted in a message that has "OST Integrity Check" as its Subject. After these instructions, ensure the sync settings are correct and check everything is working well.