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- Outlook known issues in the October 2019 updates
- Outlook Known issues in December 2024 updates
- Outlook Known issues in April 2023 updates
- VBscript does not run or you receive malicious code warning when using a custom form for Outlook
- Outlook Known issues in May 2024 updates
- Can't open Enterprise Vault items

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.
Outlook known issues in the October 2019 updates
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 resolve Outlook not sending emails fast is a new version of outlook that is web based, but still works like an app, and has less problems.
Outlook Known issues in December 2024 updates
This happens to accounts that are configured in the iOS Mail app. 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 message below to indicate it is not using the Windows Search service. 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. If you've already clicked the Accept button in Outlook 2016, you won't be able to re-accept the invitation from another Outlook application.
Outlook Known issues in April 2023 updates

If the check box is cleared, the service or startup program doesn't run when you restart the computer. You can also add the secondary connected accounts (Gmail, Yahoo, etc.) in Outlook.com as additional accounts in the Outlook Outlook stuck updating folders solution profile. 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.

VBscript does not run or you receive malicious code warning when using a custom form for Outlook
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. This occurs because custom form script is now disabled by default. You must have at least three user accounts on the computer to complete these steps. You can automatically repair your Office program files to resolve such problems as Outlook freezing or not responding. Outlook forwards meeting invitations to other attendees without anyone actually sending an update or forwarding an invite.
- 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 the check box is cleared, the service or startup program doesn't run when you restart the computer.
- After updating Office, you may experience a brief flashing window every hour, which triggers the OfficeBackgroundHandlerRegistration task to start running.
- Outlook 2016 freezes when you try to preview an Excel file that's attached to an email.
- If the network is performing slowly, Outlook must wait for read and write operations to the AppData directory to finish.
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.
Can't open Enterprise Vault items

User profiles help make sure that your personal preferences are used when you log on to Windows. As your mailbox size increases, more resources are required to open each folder. If you have a large number of items in any single folder, you may experience performance issues online Outlook email repair utility during certain operations.