In the meantime, please use the workarounds suggested for each issue. For persistent issues, use FixTechGuide’s automated tools to perform deep diagnostics and security checks. Stay updated, back up regularly, and enjoy uninterrupted productivity in your Outlook workspace. This process checks for structural issues and automatically fixes them. After the repair, reopen Outlook to confirm successful startup.

Disable Hardware Graphics Acceleration

Find solutions to common problems or get help from a support agent. Please install the Windows 10 Fall Creators Update to fix this issue. Outlook 2016 freezes when you try to preview an Excel file that's attached to an email. After updating Office, you may experience a brief flashing window every hour, which triggers the OfficeBackgroundHandlerRegistration task to start running.

Do you see the message "This set of folders could not be opened"?

• Currently, you can't use Outlook on Windows to edit calendars that are shared with your Outlook.com account, even if you've reconnected your Outlook.com account to Outlook.
• Stay updated, back up regularly, and enjoy uninterrupted productivity in your Outlook workspace.
• We're working to make it possible to edit shared calendars in Outlook 2016 for Windows.
• Fortunately, most of these errors stem from configuration conflicts, corrupted data files, or outdated components that can be fixed with a few targeted steps.
• Most startup failures arise from minor configuration mismatches or outdated components.
• Safe Mode allows you to start Outlook with all extensions temporarily disabled.

In this guide, FixTechGuide explains the top causes and provides simple step-by-step solutions to help you fix Outlook not opening on Windows 11 quickly. Until you can install the Windows Update fix release, you can set a registry key expert Outlook tips by FixTechGuide 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 message below to indicate it is not using the Windows Search service.

Outlook known issues in the Jan 2018 updates

The loading of unregistered MAPI services has been disabled by default to make Outlook more secure. To edit a shared calendar, go online to your own Outlook.com calendar, open Calendar for Windows 10, or use a mobile device. Read how to Add your Outlook.com account to another troubleshoot Outlook synchronizing folders error mail app.

Outlook known issues in the November 2019 updates

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 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. Here is a comprehensive list of possible causes for the error ‘Outlook inbox not updating’ and how they can affect the working of Outlook.



If you manually type in the secondary connected account email address in the "From" field, the email is sent as "On behalf of" your primary Outlook.com account. Please install the latest updates on your phone to resolve the issue. Outlook forwards meeting invitations to other attendees without anyone actually sending an update or forwarding an invite. This happens to accounts that are configured in the fix MFA prompts not working iOS Mail app. The issues documented in this section have been reported after installing the recent updates listed below. We're investigating the issues and will update this page when a fix is available.





We're working to make it possible to edit shared calendars in Outlook 2016 for Windows. After installing the September Public Update, Outlook 2007 displays mixed languages in the user interface. Upgrade to Microsoft Edge to take advantage of the latest features, security updates, and technical support. The folder may have been deleted or the server where the folder is stored may be unavailable. You don't have appropriate permission to perform this operation.





You might need to set Windows Update to automatically download and install recommended updates. Installing any important, recommended, and optional updates can often correct problems by replacing out-of-date files and fixing vulnerabilities. To install the latest Windows and Office updates, click the link below. This often resolves startup errors caused by configuration issues.

FixTechGuide’s free email diagnostic tools automate error detection by scanning your configuration files, registry entries, and mail protocols. The platform validates SMTP, IMAP, and POP3 settings against verified databases to identify version mismatches or broken profiles introduced after system updates. You can also add the secondary connected accounts (Gmail, Yahoo, etc.) in Outlook.com as additional accounts in the Outlook profile. To access the calendar shared with your Microsoft 365 for business account, you'll need to accept the invitation from Outlook on the web, iOS, or Android.