Colour in External Recipient Warning Banner Does not change in Outlook for Windows but changes in outlook web

Priyamvada Ajithkumar 0 Reputation points

I am experiencing an issue with the warning banner color for external recipients in Microsoft Outlook. When I configure the warning banner color for emails sent to external recipients in Outlook Web, the changes take effect as expected, and the banner displays in the specified color. However, in Outlook for Windows, the warning banner color remains unchanged, and it continues to display in the default color. And we continue to receive emails without the background colour for banner.

Steps taken to reproduce the issue:

Accessed Outlook Web as an admin user.

Navigated to the "Exchange admin center" > "Mail flow" > "Rules."

Created a new rule to add a warning banner for emails sent to external recipients.

Specified a custom color (e.g., red) for the warning banner.

Saved the rule and verified that the warning banner appears in the specified color when using Outlook Web.

After performing this, the warning banner color remains unchanged in Outlook for windows. The banner continues to display in the default color, regardless of the color settings applied in the Exchange admin center.

Is there a known issue with warning banner colors not updating correctly in Outlook for Windows, even when configured correctly in Outlook Web? Are there any additional configurations or settings that I might be missing to get the custom warning banner color to work correctly in Outlook for Windows?

Any insights or suggestions to resolve this issue would be greatly appreciated.

Thank you!

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  1. Kael Yao-MSFT 36,516 Reputation points Microsoft Vendor

    Hi @Priyamvada Ajithkumar

    Thanks for the information.

    Please modify the condition to:

    <div><span style="background:aqua">CAUTION:This email originated from an external sender.Do not click links r open attachments unless you are expecting the email and know the contents is safe.</span></div><br>

    And see if it can work for you.

    Below is the result based on my test:


    In Outlook ((Version 2306 Build 16.0.16529.20164) 64-bit):


    In OWA:


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