Power Platform Community Forum Thread Details

How to assign x-www-form-urlencoded type parameters to an empty body in a custom connector?

My requirement is to add a POST request to a custom connector. This request has a Content-Type of application/x-www-form-urlencoded. After adding it, I found that the input parameters must be in JSON format. Then I found the following article that solved the problem by using {}.

How to use form-urlencoded content type in Power Automate Custom Connector – Mohamed Ashiq Faleel

But when following the guidance in that article and assigning values to the body in Power Automate, I created a Compose action just like it suggested, encoding all the values and separating them with &. However, after sending the request, I got a 404 error. Please help me resolve this issue with the value assignment. Below, I’ve included some detailed points I discovered during testing

When testing this API in the custom connector, you need to enable the body as raw body; otherwise, it will also return a 404 error.

So another possible solution is to figure out how to input the body in Power Automate using a raw body approach. However, I’ve checked and it seems there’s no way to do that. I feel the core issue is that Power Automate automatically wraps the request with an extra layer. Could the experts please take a look and suggest any good workaround?

In Power Automate, the value assigned in Compose is:
startDate=@{encodeUriComponent('2025-10-03')}&endDate=@{encodeUriComponent('2025-10-03')}.