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. If you haven't installed alternative security software, you should temporarily turn off Windows Defender Security Center. Test other credential loop in Microsoft 365 programs or websites to be sure Outlook is the only problem.

Method 4: Recreating the Outlook Profile

Another which is shown below, is a user opens a new message, or replies to one, and lets it sit for a while. When they go back to the message and press send they get an error that the message has been deleted. Ive repaired the OST and changed cache online Outlook email repair utility mode to only cache 1 year.

Check the connectivity to your email server

• We have shared five manual methods in this blog to resolve the Outlook syncing errors.
• The client has a computer off the domain at home that his work email is tied to and he has never had any of these issues in Cache mode with that device.
• Once the client started using Outlook again after some time has passed the issue had come back.
• When they go back to the message and press send they get an error that the message has been deleted.
• After these instructions, ensure the sync settings are correct and check everything is working well.
• The other solution to fix Outlook sync issues is recreating Microsoft Outlook profile.

When the user is signed into their mobile app, webmail, or the FixTechGuide email error solutions Windows Mail app, they are able to receive email perfectly fine with those. The issue is occurring only in the Outlook program installed on Windows. To update from Azure AD Sync to Microsoft Entra Connect, see the upgrade instructions.

Methods to fix Microsoft Outlook syncing error

I ran the PSTscan tool to check for anomalies on the OST file (which it found and repaired but the issue still occurs). However, with one particular client no matter what changes are made these sync issue still occur. We're sorry you're having problems with the Mail and Calendar apps for Windows 10. To fix the issue, please try each of the following solutions in order.

Microsoft Outlook Sync issues

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. Moreover, it maintains the folder hierarchy and metaproperties of the data when processing Outlook data files.