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. You don't have permission to create an entry in this folder. Right-click the folder, and then click Properties to check your permissions for the folder. See the folder owner or your administrator to change your permissions. 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.

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.
• This ensures Outlook and Windows run the same DLL versions and registry references.
• The person who sent you the invitation will need to remove your permissions and then send a new invitation.
• Fortunately, most of these errors stem from configuration conflicts, corrupted data files, or outdated components that can be fixed with a few targeted steps.
• If you can't choose any of the menu options, type inside an email message, calendar event, or contact, Outlook may have frozen.
• Most startup failures arise from minor configuration mismatches or outdated components.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 Troubleshoot Office 365 Sync and Login Issues 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 how to fix Outlook not opening today mail app.

Outlook known issues in the November 2019 updates

Once the scan completes, reopen Outlook and check if the issue is resolved. Go to File → Options → Add-ins → disable all add-ins, then re-enable them one by one to find the faulty one.



If you've already clicked Outlook Stuck on Synchronizing Folders the Accept button in Outlook 2016, you won't be able to re-accept the invitation from another Outlook application. The person who sent you the invitation will need to remove your permissions and then send a new invitation. 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.

Windows Command prompt running OfficeBackgroundHandlerRegistration task flashes every hour

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.

Outlook Known issues in February 2024 updates

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.

Note that you can quickly tell how your mail is currently sorted, by the presence of a small triangle on the field headers. Another options is to use the Filter Email button on the ribbon. You may notice that All, Unread , Mentioned and other sort and filtering options, such as By date, and Newest are missing in Outlook above your email list.