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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

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 Quick Access Toolbar. 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. We're working to make it possible to edit shared calendars in Outlook 2016 for Windows.
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 Outlook Stuck on Synchronizing Folders 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 recreate Outlook profile step by step 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 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.
- This issue affects all Outlook versions on Windows 7, Windows 8, Windows 10.
- 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.
- 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.
- 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.
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 fix MFA prompts not working 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.