The built-in search will display the message below how to fix Outlook not opening today to indicate it is not using the Windows Search service. The issues documented in this section have been reported after installing the recent updates listed below. We're investigating the issues and will update this page when a fix is available. In the meantime, please use the workarounds suggested for each issue. 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.

Troubleshooting Co-Authoring and Collaboration Errors

• Select the corrupted PST or OST using the file picker.
• When they get too large, go corrupt, or are poorly configured, things start to break.
• The issues documented in this section have been reported after installing the recent updates listed below.
• Your antivirus software can also cause issues with Outlook connectivity.
• Corrupted or badly set-up Outlook profiles can often cause start-up problems.
• Microsoft Outlook is one of the best-known business-class email clients from Microsoft.

Check your antivirus software’s settings and ensuring Outlook is listed as a trusted application. The colleagues at Bleeping Computer noticed this update and addressed it in this post. This post also mentions the downgrade to an earlier Microsoft 365 build, which was previously described as a workaround.

Get Expert Help from TrustedTech

Microsoft had confirmed the issue for Windows Server 2016 and 2019 and recommended a downgrade. With apps syncing across devices and cloud services, sync issues are among the most frequently reported M365 problems. These can include missing files, ghost icons, or documents that do not update in real-time. You can also add the secondary connected accounts (Gmail, Yahoo, etc.) in Outlook.com as additional accounts in the Outlook profile.

Outlook Known issues in April 2023 updates

When built-in tools fall short, professional solutions pick up the slack. Using Cached Exchange Mode in complex environments can lead to painful sync delays. If a user has a large mailbox or lots of folder nesting, syncing might lag or even crash. Let’s look at what causes Outlook to crash, how you can fix it, and a smarter tool that takes a lot of the stress off your plate. Find solutions to common problems or get help from a support agent. The folder may have been deleted or the server where the folder is stored may be unavailable.

Outlook Known Issues in November 2021 updates

Corrupted or badly set-up Outlook profiles can often expert Outlook tips by FixTechGuide cause start-up problems. The app might refuse to launch or crash at the splash screen. Outlook slows down, crashes randomly, or fails to load entirely.



We're working to make it possible to edit shared calendars in Outlook 2016 for Windows. Not Implemented Error mostly appears in Outlook 2010, 2013, 2016, 2019 and latest Microsoft 365 version. Boost your SMB’s security and compliance with Microsoft 365 Business Premium. Discover Defender and Purview add-ons for enterprise-grade protection at SMB-friendly pricing. In these cases, direct escalation to Microsoft or working with a Microsoft CSP partner, such as FixTechGuide support for Office 365 TrustedTech, can expedite resolution and minimize downtime. Our licensing engineers can help triage complex problems and ensure you're on the right support path.