Classic Outlook Current Channel 2602 does not render Adaptive Cards in email (works in Monthly Enterprise, OWA and iOS)

Question

Hello,
We are experiencing a rendering issue with Adaptive Cards embedded in email using:
HTML: <script type="application/adaptivecard+json">

Environment:

• Microsoft 365 Apps for enterprise
• Classic Outlook (Win32)
• Current Channel
• Version 2602 (Build 19725.x)
• Windows 11 x64

Problem:

In Classic Outlook on Current Channel 2602, Adaptive Cards embedded in email do not render. The email either shows only fallback text or appears blank. This happens regardless of whether we use Adaptive Card schema version 1.0, 1.2, 1.3 or 1.4.

What works:

New Outlook (Windows) – renders correctly

Outlook on the web – renders correctly

Outlook for iOS – renders correctly

Classic Outlook on Monthly Enterprise Channel (Version 2512, Build 19530.x) – renders correctly

What does not work:

Classic Outlook on Current Channel 2602

We tested:

Multiple card schema versions (1.3, 1.4)

Cards with and without inputs and Action.Http

Different originator IDs

Minimal test cards (TextBlock only)

Behavior appears specific to Classic Outlook on Current Channel 2602.

Question:

Is there a known regression in Current Channel 2602 related to rendering of Adaptive Cards / Actionable Messages in Classic Outlook? Has this been fixed in 2603 or a later build?What works:

New Outlook (Windows) – renders correctly

Outlook on the web – renders correctly

Outlook for iOS – renders correctly

Classic Outlook on Monthly Enterprise Channel (Version 2512, Build 19530.x) – renders correctly

What does not work:

Classic Outlook on Current Channel 2602

We tested:

• Multiple card schema versions (1.0, 1.2, 1.3, 1.4)

Cards with and without inputs and Action.Http

Different originator IDs

Minimal test cards (TextBlock only)

Behavior appears specific to Classic Outlook on Current Channel 2602.

Question:

Is there a known regression in Current Channel 2602 related to rendering of Adaptive Cards / Actionable Messages in Classic Outlook?
Has this been fixed in 2603 or a later build?

Answer 1

Hello Jack-Bu

Thank you for testing on Version 2601- that aligns with our findings and further suggests a regression introduced in 2602.

We can consistently reproduce the issue on Current Channel 2602 across multiple clients, while the same cards render correctly in 2512 Monthly Enterprise Channel.

We will proceed with opening a Microsoft 365 admin support ticket to allow log collection and escalation to the Product Team.

I will update this thread once we receive confirmation from support.

Answer 2

Hi Kasia Persson, 

Welcome to Microsoft Q&A Forum!

Have a good day and I hope you're doing well!

Thank you for providing such a detailed report and isolating the issue across different channels and platforms. I understand how disruptive it is when Adaptive Cards stop rendering in your primary workflow, especially when they function correctly elsewhere. 

Based on my research, I have not yet found any official public announcements or known issues regarding a specific regression in Current Channel Version 2602 for Adaptive Cards. 

To investigate further, I performed a test in a slightly older environment running Classic Outlook Version 2601 (Build 19528.20214), and I confirmed that Adaptive Cards are still rendering and functioning correctly there. This strongly supports your finding that the behavior is likely specific to the 2602 update. 

1. While waiting for a potential fix in a future build, I recommend continuing to use Outlook on the Web (OWA) or the New Outlook for Windows as immediate alternatives.

2. If staying on Classic Outlook is critical for your operations, you can temporarily revert (rollback) your Office installation to the previously stable version.  

You can follow the detailed instructions here: How to revert to an earlier version of Office 

Since you have already performed thorough troubleshooting (testing minimal cards, schemas, and excluding custom edge cases) and confirmed this is a client-specific rendering issue, I highly suggest raising a support ticket. 

This will allow the Microsoft Support team to arrange a remote session to capture logs and validate the reproduction directly on your Version 2602 environment. This is the most effective way to escalate this potential regression to the Product Team. 

Instructions for your IT Admin to raise a ticket: Get support - Microsoft 365 admin 

I hope this information helps you navigate the issue. If you have any questions, concerns, or if anything is unclear, please feel free to let me know. 

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