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 OST vs PST repair 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.

Turn off Windows Defender Security Center

If the size of your .ost file is close to the limit, you could try increasing the limit on your client, restart Outlook and see if there is any difference. Outlook profile repair and recovery steps I’ve unchecked download shared folders when setting up a new Outlook profile. 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.

Check if two-factor authentication is turned on for your account

Once the client started using Outlook again after some time has passed the issue had come back. I ran the PSTscan tool to check for anomalies on the OST file (which it found and repaired but the issue still occurs). I’ve tried to set cache mode from 1 year all the way down to a few days.

Check Antivirus and Firewall Settings

• Before we know the solutions, we will understand a few common causes of the Outlook sync problem.
• 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.
• There are various methods to resolve the Outlook sync issues, including manual and third-party solutions.
• Now, we will verify the server settings to fix the Outlook synchronization error.

However, in some situations these processes can take up to 24 hours. We're in the process of migrating from On-Premise Exchange to O365. I fix MFA prompts not working have a couple of Users and a Shared Mailbox that were migrated and both Users are experiencing issues with the Shared Mailbox updating on a regular basis.

Free Methods to Remove Duplicate Items in Outlook 2016

If you're using an Exchange account that requires advanced settings, you'll need to remove the account and add it again using advanced settings. To add the account using advanced settings, see Add an account using advanced setup. Knowing the reasons behind the Outlook sync issues will help us to fix this problem and prevent issues in communication and workflow. If you still can't sync your email after removing your account and adding it again, you might need to add the account using advanced setup. If I check the sync log I see a lot of sync errors for Inbox, sent items and a few other folders.