Outlook not running 365 version

Question

PC is subscribed to Microsoft 365 but Outlook is using

Microsoft Outlook Version: 1.2025.1020.100

Client Version: 20251031008.17

WebView2 Version: 142.0.3595.53

Session ID: 8d2a4650-2b6f-784a-a257-1ef20f5423ff

Trying to open some emails generates error message, requiring 365 version.

Moved from: Microsoft 365 and Office | Access | For home | Windows

Answer 1

It appears that you are using an outdated version of Outlook that may not be compatible with certain features or emails that require the latest Microsoft 365 version. To resolve this issue, you should update your Office installation to the latest version. Here’s how you can do that:

1. Open any Office application, such as Outlook or Word.
2. Select File, and then select Office Account or Account.
3. Check the version number listed under Office Updates. If it is earlier than the latest version, select Update Options, and then select Update Now.

Updating to the latest version should help resolve the error messages you are encountering when trying to open emails.

If the issue persists after updating, consider troubleshooting further by checking for any add-ins that may be causing conflicts or running the Microsoft Support and Recovery Assistant for additional diagnostics.

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References:

• Can't send or receive email in Outlook and "Metered Connection Warning" is triggered
• How to troubleshoot issues that cause Outlook to crash or stop responding when used with Microsoft 365

Answer 2

Hello Anne,

Thank you for reaching out I understand you're experiencing an issue where Outlook is not running the Microsoft 365 version despite your PC being subscribed to Microsoft 365. I can imagine how frustrating it must be to encounter errors when trying to open emails especially when you're expecting full compatibility with your subscription.

This situation often arises when the installed Outlook version is not aligned with the Microsoft 365 apps suite which can lead to limitations in accessing certain features or content.

To address this instead of simply updating Office another effective resolution is to ensure that you're using the New Outlook for Windows which is designed to work seamlessly with Microsoft 365. You can switch to the new Outlook experience by opening Outlook selecting the toggle in the upper right corner labeled “Try the new Outlook,” and following the prompts to complete the setup. This version is optimized for Microsoft 365 and resolves many compatibility issues including those related to email rendering and feature access. If you're already using the new Outlook and still facing issues it may help to run Outlook in Safe Mode to check for conflicting add-ins or use the Microsoft Support and Recovery Assistant (SaRA) tool to diagnose and fix deeper configuration problems.

Could you let me know if you've already tried switching to the new Outlook or running diagnostics?

I hope this answer is helpful if you have further questions feel free to reply back

Regards,

Marcelo