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. The other solution to fix Outlook sync issues is recreating Microsoft Outlook profile. Sometimes an error appears in the Mail and Calendar apps when the apps try to sync new email or calendar events.

The client has a computer off the domain at home that his work email is tied to and he has never had any flush DNS and re-sync Outlook of these issues in Cache mode with that device. 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. Select the button below to launch a diagnostic in the Microsoft 365 admin center.

• I ran the PSTscan tool to check for anomalies on the OST file (which it found and repaired but the issue still occurs).
• Windows Defender Security Center is free security software that's included with Windows 10.
• Outlook sync issues can be because of corrupted Outlook OST or PST files.
• If your password is incorrect, you'll see a message asking you to update your password.
• To solve your Outlook issues, download the application from the Microsoft website and follow the directions.
• After the files get repaired, restart the Outlook program to ensure that the Outlook syncing issues are resolved or not.

How to Fix Sync Issues in Outlook or OWA? – A Complete Guide

Check the software documentation to learn how to temporarily turn it off. Firewalls and antivirus software might prevent you from syncing your email and calendar events. There are various methods to resolve the Outlook sync issues, including manual and third-party solutions.

Professional automation to resolve Microsoft Outlook syncing issues

Before we know the solutions, we will understand a few common causes of the Outlook sync problem. The most common cause of an out-of-date account is an incorrect password. In the notification bar at the top of the app, select Fix account.

Method 5: Fixing Sync Issues in Outlook Web Access (OWA)

I’ve tried to set cache mode from 1 year all the way down to a few days. However, with one particular client no matter what changes are made these sync issue still occur. After these instructions, ensure the sync settings are correct and check everything is working well. To make sure there are no issues, click Test Account Settings to test the connection. Test other programs or websites to be sure Outlook is the only problem.

Delays in provisioning of user/mailbox or synchronizing changes in Exchange Online

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. 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. This software allows users to process numerous OST files at once without any size limitations.





After the files get repaired, restart the Outlook program to ensure that the Outlook syncing issues are resolved or not. I still have it turned on on FixTechGuide mailbox repair steps my laptop and it has not shown any issues yet. However I do not use Outlook on it as much as I do on my desktop.

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Once you have completed the steps to fix Outlook sync errors, kindly check if the error has been fixed or not. If your password isn't the problem, you might have a certificate error. If so, you'll see a message that says, "There is a problem with the server's security certificate. The security certificate is not from a trusted certifying authority." Check with your email provider for instructions about how to create an app password for your email account. If you can sync your email when the firewall is turned off, you'll need to allow the Mail and Calendar apps through the firewall. Windows Defender Security Center is free security software that's included with Windows 10.

These are the only two I've seen have this issue and I was wondering if you've seen this and figured out a 'fix'? Tempted to create a Test Shared Mailbox, but thinking that wouldn't be an accurate test for inbound mail, etc. or just actually tested by the Users at all. Upgrade to Microsoft Edge to take advantage of troubleshoot office 365 sync and login issues the latest features, security updates, and technical support.

Reconfigure Server Settings

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. 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.