web
You’re offline. This is a read only version of the page.
close
Skip to main content

Announcements

Welcome to the Power Platform Communities
News and Announcements icon
Community site session details

Community site session details

Session Id :
Power Platform Community / Forums / Power Automate / Custom Connector Expre...
Power Automate
Answered

Custom Connector ExpressionEvaluationFailed

(0) ShareShare
ReportReport
Posted on by Fvamaro 45

I'm developing an app connection with Microsoft Flow.

My app is a document management app (created by me) and the goal is foir example to upload a file from my app to One Drive, using flows.

 

I've already crated a connector ( I submited my Web API and tested it successfully).

 

When I tried to create a flow with my connector it returns me the following errror: 

 

ExpressionEvaluationFailed. The execution of template action 'Apply_to_each' failed: the result of the evaluation of 'foreach' expression '@triggerBody()?['value']' is of type 'Null'. The result must be a valid array.

 

What I must do to fix it?

Categories:
General topics
  • Verified answer
    v-micsh-msft Profile Picture
    v-micsh-msft Microsoft Employee on at

    Hi @Fvamaro,

     

    The error message means the Value Content inputted under the Apply to Each has no values.

    What is the data returned by your custom connector?

    In addtion, would it be available for you to share a screenshot of the flow configuration details?

    Which should be helpful for me to share a further suggestion.

     

    If the returned type is an array, then we could take use of the empty() function to check if it has value first.

    Formula under the condition Advanced option should be something like:

    @empty(Body()?['value'])

     

    Then under the No part, add the Apply to Each.

     

    Regards,

    Michael

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

Quick Links

Season of Sharing Community Challenge Winners!

Congratulations to our community stars!

Kudos to our 2025 Community Spotlight Honorees

Expanding mentorship, skilling, and AI innovation

Congratulations to the August Top 10 Community Leaders!

These are the community rock stars!

Leaderboard > Power Automate

#1
Mohsin Ali Profile Picture

Mohsin Ali 355

#2
11manish Profile Picture

11manish 336 Super User 2026 Season 2

#3
M Bilal Khan Profile Picture

M Bilal Khan 308

Last 30 days Overall leaderboard

Featured topics

Known issue with browser automation in Power Automate for Desktop on Google Chrome 146 and 147
Share your ideas and struggles with building Power Automate flows!
Survey: Power Automate mobile app
How to Ask for Help with Your Power Automate Workflow
Start and wait for an approval action
Restore a deleted flow
List of actions cheat sheet for Power Automate Desktop
Welcome to the Power Automate forum!

Product updates

Microsoft Power Platform Community release plans