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. Maybe you've added a new program to your computer that doesn't get along with Outlook, or your system has a virus. Regardless of the specific cause, there are several key troubleshooting fixes to try that might help. If your antivirus software isn't up-to-date, Outlook may not function correctly. Outlook stores certain data, such as email signatures and the spelling checker dictionary, in the AppData folder.

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If so, wait a short time (usually two or three minutes) to see if Outlook starts working again. If you can't choose any of the menu options, type inside an email message, calendar event, or contact, Outlook may have frozen. There are three steps you can take to try to get Outlook working again. For more information, see How to install the latest applicable updates for Microsoft Outlook (US English only). There Outlook OST vs PST repair is a new version of outlook that is web based, but still works like an app, and has less problems.

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The person who sent you the invitation will need to remove your permissions and then send a new invitation. Occasionally, classic Outlook tries to run a process in the background. Auto-archive, sending and receiving a very large attachment, or running some of the other mailbox tools can all be done in the background. Check the status bar at the bottom of the screen to see if another process is running.

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When you install Outlook, an Inbox repair tool (scanpst.exe) is also installed on your PC. The Inbox repair tool can resolve problems by scanning your Outlook data files, and fix MFA Prompts not working repairing errors. To use the Inbox repair tool, exit Outlook, and then follow the steps in Repair Outlook Data Files (.pst and .ost). If your antivirus software includes integration with Outlook, you may experience performance issues. You can disable all Outlook integration within the antivirus software.

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If the network is performing slowly, Outlook must wait for read and write operations to the AppData directory to finish. To manage your mailbox by reducing the size of the Outlook data file, see Reduce the size of Outlook Data Files (.pst and .ost). Although add-ins can enhance your user experience, they can occasionally interfere or conflict with Outlook.

• You may have to contact your antivirus software vendor to determine how to configure the software to exclude any integration with Outlook or to exclude scanning in Outlook.
• You don't have appropriate permission to perform this operation.
• If you have a large number of items in any single folder, you may experience performance issues during certain operations.
• 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.
• In the meantime, please use the workarounds suggested for each issue.
• In System Configuration, if you select a check box, the related service or startup program runs when you restart the computer.
• 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.
• For more information, see How to install the latest applicable updates for Microsoft Outlook (US English only).

Outlook Known issues in May 2024 updates

Here are some common fixes that should work when Outlook doesn't open, whether you're using Windows or a Mac. To manage your mailbox by using the AutoArchive feature, see AutoArchive settings explained. We recommend that you move several items in your larger folders to separate folders, or that you archive those items by using the AutoArchive feature. These steps are provided in a specific order based on commonality and complexity. Find solutions to common problems or get help from a support agent.





For more information, see Outlook performance issues when there are too many items or folders in a cached mode .ost or .pst file. To create a user profile, you must first create a user account. To determine whether this problem is caused by a corrupted user profile, create a user profile to see whether the problem still occurs when you use the new profile. To keep up with new viruses as they're created, antivirus software vendors periodically provide FixTechGuide email error solutions updates that you can download from the Internet. Download the latest updates by visiting your antivirus software vendor's website. Please install the latest updates on your phone to resolve the issue.