Skip to main content

Notifications

Announcements

Welcome to the Power Platform Communities
Check out the New Agent Creator Community
News and Announcements icon
Community site session details

Community site session details

Session Id :
Power Platform Community / Forums / Power Automate - Building Flows / “Message text mention ...
Power Automate - Building Flows
Unanswered

“Message text mention needs to be specified” on the action “Post a message in a chat or a channel” (Power Automate / Teams)

(0) ShareShare
ReportReport
Posted on by Azélie 2

Hello

I ask for your help for an error on a particular action on Teams.

I have a Power Automate flow, which post particular messages on several channels. But on one of these channels I have an error, with the following message : “Message text mention needs to be specified”. What are the possible reasons of this message ?

Erreur-constatée.JPG

I have verified the account used for the execution of this flow. He can write properly on this channel manually. He can send a small message to this channel with the action “Post a message in a chat or a channel”.

But the message, which is prepared in my flow and sent with this action, is a long message written in HTML.

Action-réduite.png

In this case it mentions an user with <at> tag. Is there a limit for the email written between <at> and </at>? How many characters could contain this email?

Thank you very much for your help

Nicole

  • HanifUzir Profile Picture
    HanifUzir 2 on at
    Re: “Message text mention needs to be specified” on the action “Post a message in a chat or a channel” (Power Automate / Teams)

    Me too! Before I found this post, I had the same error, then applied the solution as suggested by @Azélie, it worked at the beginning for a while like for all new posts ever since the fix. Until recently, the same kinda post returns the same error message back to square one. I have a feeling this happened right after the recent Power Automate update from Microsoft at the new designer where the pane to edit the flow appears on the left side of the cards. Any thoughts?

  • ndawoodani Profile Picture
    ndawoodani 2 on at
    Re: “Message text mention needs to be specified” on the action “Post a message in a chat or a channel” (Power Automate / Teams)

    I got the same error when I used Channel email address between <at></at> tags. The length of the email is 36 char and I got the email id using the 3 dots on channel and using option "Get email address" 

    I also tried getting User Profile using the same email id but that does not work either. How can I solve this?

    ndawoodani_0-1700508277614.png

     

  • Azélie Profile Picture
    Azélie 2 on at
    Re: “Message text mention needs to be specified” on the action “Post a message in a chat or a channel” (Power Automate / Teams)

    Hello,

    In my flow the user was mentioned with his email and the <at> tag. And there was an error when the email of the user is very long (42 characters). I thought this email could not be interpreted.

    So I get the User ID (Microsoft 365) with the “Get User Profile” action. I mention the user with his User ID between <at> and </at>. There is no more error on my flow

    Best Regards

    Nicole

Under review

Thank you for your reply! To ensure a great experience for everyone, your content is awaiting approval by our Community Managers. Please check back later.

Helpful resources

News and Announcements

Welcome to the Power Platform Communities
Check out the New Agent Creator Community

Quick Links

Michael Gernaey – Community Spotlight

We are honored to recognize Michael Gernaey as our June 2025 Community…

Congratulations to the May Top 10 Community Leaders!

These are the community rock stars!

Announcing the Engage with the Community forum!

This forum is your space to connect, share, and grow!

Leaderboard >

Last month Overall leaderboard

Featured topics

Start and wait for an approval action

Product updates

Microsoft Power Platform Community release plans