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"?

• This often resolves startup errors caused by configuration issues.
• Auto-archive, sending and receiving a very large attachment, or running some of the other mailbox tools can all be done in the background.
• You don't have permission to create an entry in this folder.
• Many users face this frustrating issue after a Windows update or due to corrupted Outlook data files.
• 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.
• When this registry key is set, Outlook will use its own built-in search engine.

There is currently no option to revert to the prior behavior, but we would love to hear your feedback to help us with future designs. To learn more about how to send us feedback, please see How do I give feedback on Microsoft Office. To access the filtering options faster, add them to your Outlook OST vs PST repair Quick Access Toolbar.

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 resolve Outlook not sending emails fast 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.

Step 3: Repair Outlook Data Files

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

This occurs because custom form script is now disabled by default. Are you struggling to open Microsoft Outlook on your Windows 11 PC? Many users face this frustrating issue after a Windows update or due to corrupted Outlook data files.

Outlook Known issues in February 2024 updates

By the end, you’ll know exactly how to restore your Outlook and prevent future errors. If your Microsoft Outlook won’t open after a recent Windows update, you’re not alone. Many users encounter startup freezes, profile loading loops, and crashes following major Windows patches or Office updates.

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.