Failed to validate the signature of the actionable message card

[schuess3]

I am unable to understand why a user started receiving the following error message:

"Failed to validate the signature of the actionable message card."

Do you have any suggestions for me?

Thanks

[anandodaniel]

No, Still can't respond via Outlook with my account. May be the best thing to do is just wait Microsoft solve the bug

[schuess3]

Unfortunately, last time it resolved on its own, aka MS Fix.

https://powerusers.microsoft.com/t5/Using-Flows/Failed-to-validate-the-signature-of-the-actionable-m...

[mco1]

I also have people at our org that started encountering this today. I checked the approval flow connections since it is built through my account and all connections are fine.

[schuess3]

Global Outage. Microsoft is working on it. 

[ChadH]

Good to know, thank you for this. 

[EWebster]

We have the same error here. Glad to know it's not just us!

[mco1]

TY!

[Haidpsabeco]

i successfully fixed it after 1 day.

[MayTTHan]

Hello, how did you fix it? I am having the same issue.

[binghua]

I met the same issue since yesterday, it was working perfectly before. I can do the approval through Approvals in Automate and Teams, the 'Failed to validate the signature of the actionable message card.' issue only happens in approval in Outlook with my account, my colleague's account has no issue with it at all.

[anandodaniel]

How? Can you share us how to fix it?

[anandodaniel]

How? Can you share us how to fix it?

[Haidpsabeco]

I am not sure about this solution because I have implemented many solutions at the same time.
Maybe the cause comes from logging in to 2 accounts at the same time. Actually the web browser has memorized my 2 accounts at the same time. And when I log out of the secondary account, everything is back to normal. (It will be a bit difficult to log out of the secondary account because I just discovered this by accident, when you go to outlook online always log in to the main account but in fact it still remembers your sub account in somewhere)..

[Amit_Sharma]

Hi @schuess3 

I can confirm this issue it's also occur with me for now you could go to power automate approval section and approve/reject all the approval request.

 Hope it helps!

[Haidpsabeco]

It may be caused by logging in to 2 accounts at the same time. You should check your web browser and log out of the other account. (It seems that microsoft edge always remembers 1 default account that is synchronized with the computer, if you log in to another account, the above will be duplicated)

[saurabh110]

Thanks @Haidpsabeco , I was logged in with two id's on chrome. I just logged off from one account and refreshed the outlook and I was able to approve/reject the request.

But strange/co-incident thing is how all of the sudden global power automate users started facing the same issue that too in the same week??

CC: @schuess3 @Amit_Sharma @anandodaniel @binghua @MayTTHan @mco1 @EWebster @ChadH 

[Haidpsabeco]

I think the main reason is Microsoft, because the email I use for approval is also the email I receive the request. There may be a mistake coming from Microsoft.
And I can only give the cause and solution for you to follow.
Glad to be able to help you

[binghua]

The issue with my account was automatically fixed by its own just now, I can do approvals in outlook client now, the reason must be in Microsoft side as I did no change in flow, just leave it to time, I've being waiting for one and a half day. 

[AMicchia]

Problably the password of you accounr MSO365 was recently changed through the Computer and not in the mobile device (smartphone/tablet). Try updating the same account on the to mobile device. I believe the issue will be resolved.

[kinggeoarge]

My Friends, 

This is the solution in my case.  Sure enough, I can duplicate and resolve now.