Upgrade to Microsoft Fix Outlook and Office365 Sync Issues Edge to take advantage of the latest features, security updates, and technical support. You can start Outlook in safe mode, disable your add-ins, and then try to open Outlook normally. The folder may have been deleted or the server where the folder is stored may be unavailable. To access the filtering options faster, add them to your Quick Access Toolbar.

• We're working to make it possible to edit shared calendars in Outlook 2016 for Windows.
• Until you can install the Windows Update fix release, you can set a registry key that will cause Outlook to stop using the local Windows Search service.
• If you typically use an Outlook.com account for email, this issue can occur if there are multiple aliases on the account and the 3rd party email address is the primary alias.
• Many users encounter startup freezes, profile loading loops, and crashes following major Windows patches or Office updates.
• The platform validates SMTP, IMAP, and POP3 settings against verified databases to identify version mismatches or broken profiles introduced after system updates.

Outlook Known issues in October 2020 updates

You can also add the secondary connected accounts (Gmail, Yahoo, etc.) in Outlook.com as additional accounts in the Outlook profile. Until you can install the Windows Update fix release, you can set a registry key that will cause Outlook to stop using the local Windows Search service. When this registry key is set, Outlook will use its own built-in search engine. The built-in search will display the reset cached Exchange mode message below to indicate it is not using the Windows Search service. This command deletes the custom folder views, restoring default configurations. It’s harmless and resolves 30% of stuck startup issues according to Microsoft community reports.

Outlook known issues in the January 2019 updates

After updating Office, you may experience a brief flashing window every hour, which triggers the OfficeBackgroundHandlerRegistration task to start running. For more information about when builds are available for their respective channels, go to Update history for Microsoft 365. We're investigating the issue and will update this page when a fix is available. MAPI does not validate that a provider's DLL guide to Office 365 sign-in errors that it is requested to load is registered correctly in MapiSVC.inf or even that it comes from the local machine. This can be exploited by creating a file together with an OLE object in such a way to cause MAPI to load a DLL from a network share when the OLE object is activated. If you're using Outlook 2010, Outlook 2013 or Outlook 2016, uninstall and re-install iCloud to resolve this issue.

Troubleshoot Outlook for Windows issues

To learn more about how to send us feedback, please see How do I give feedback on Microsoft Office. Note that you can quickly tell how your mail is currently sorted, by the presence of a small triangle on the field headers. Outlook 2016 freezes when you try to preview an Excel file that's attached to an email. This issue affects all Outlook versions on Windows 7, Windows 8, Windows 10.

Outlook Known issues in March 2025 updates

Stay updated, back up regularly, and enjoy uninterrupted productivity in your Outlook workspace. Online Repair reinstalls Outlook components while preserving your data, resolving DLL and registry mismatches that prevent startup. This process checks for structural issues and automatically fixes them. Occasionally, classic Outlook tries to run a process in the background.

Outlook issues after connecting Outlook to Outlook.com

Third-party add-ins are among the most common culprits for Outlook not opening properly. Safe Mode allows you to start Outlook with all extensions temporarily disabled. The only other change to the Exchange Server was a certificate update for IIS. This is a standard DigiCert wildcard cert that we have replaced every year with no issues.