HTTP request trigger failed – The HTTP request trigger could not be processed.

The HTTP request trigger in Power Automate allows flows to start when an HTTP request is received. However, sometimes users encounter the following error:

“HTTP request trigger failed – The HTTP request trigger could not be processed.”

This means that the HTTP trigger was unable to execute due to issues such as incorrect configurations, authentication failures, API limits, or network-related problems.

2. Causes of the “HTTP Request Trigger Failed” Issue

Several factors can cause this issue:

Incorrect HTTP Method – If the request is sent using the wrong method (GET, POST, PUT, DELETE), the trigger may fail.
Invalid or Expired URL – If the trigger URL is incorrect or has changed, the request cannot reach the flow.
Missing or Incorrect Headers – If required headers (such as Content-Type or Authorization) are missing or incorrect, the request will be rejected.
Invalid JSON Payload – If the request body is not formatted correctly in JSON, the trigger will fail.
Authentication Issues – If the HTTP request requires authentication and the credentials are missing or incorrect, the flow will be blocked.
Power Automate Plan Limitations – If your Power Automate plan does not support premium connectors, the HTTP trigger may not work.
API Throttling or Rate Limits – If too many requests are made in a short time, Microsoft may temporarily block incoming requests.
Firewall or Network Restrictions – If the request is blocked by a corporate firewall, security policy, or proxy, it will not reach Power Automate.
Microsoft Service Downtime – If Power Automate services are experiencing delays or outages, HTTP requests may fail.
Incorrect Environment or Region – If the flow is hosted in a different region than expected, the request may not reach the correct endpoint.

3. Step-by-Step Troubleshooting Guide

Step 1: Verify the HTTP Trigger URL

Open Power Automate (https://flow.microsoft.com).
Go to My Flows and find the affected flow.
Click Edit and open the HTTP Request Trigger.
Copy the Trigger URL and compare it with the URL used in the failed request.

✅ Correct Example:

https://prod-00.westus.logic.azure.com:443/workflows/{flow-id}/triggers/manual/paths/invoke

❌ Incorrect Example (Expired or Modified URL):

https://prod-00.eastus.logic.azure.com:443/workflows/{wrong-id}/triggers/manual/paths/invoke

If the URL is incorrect, update it in the external application or script making the request.

Step 2: Check the HTTP Method (GET, POST, PUT, DELETE, PATCH)

Power Automate HTTP triggers expect a specific HTTP method (e.g., POST).
If the request is sent with an incorrect method, the trigger may not process it.

✅ Correct Example (Using POST method):

POST https://prod-00.westus.logic.azure.com:443/workflows/{flow-id}/triggers/manual/paths/invoke

❌ Incorrect Example (Using GET method instead of POST):

GET https://prod-00.westus.logic.azure.com:443/workflows/{flow-id}/triggers/manual/paths/invoke

To fix this, modify the HTTP request method in the application or script sending the request.

Step 3: Validate Headers and Content-Type

Some HTTP triggers require specific headers, such as Content-Type. If these are missing or incorrect, the request will fail.

✅ Correct Headers:

Content-Type: application/json
Authorization: Bearer {access-token}

❌ Incorrect Headers:

Content-Type: text/plain  ❌ (Should be JSON)
Authorization: Basic {wrong-token}  ❌ (Incorrect authentication method)

Ensure the Content-Type header is set to application/json.
If authentication is required, include the correct Authorization header.

Step 4: Verify JSON Payload Formatting

If the request body contains JSON data, ensure it is formatted correctly.
An incorrectly formatted JSON payload will result in a failed trigger.

Correct JSON Format:

{
  "name": "John Doe",
  "email": "john.doe@example.com"
}

Incorrect JSON Format (Missing Quotes or Comma):

{
  name: "John Doe",
  email: "john.doe@example.com"
}  ❌ (Property names must be in quotes)

Use a JSON validator (e.g., https://jsonlint.com) to check for errors.

Step 5: Check Authentication and Permissions

If the HTTP request requires authentication, ensure that valid credentials or tokens are provided.
If using Azure Active Directory (AAD) authentication, verify that the token is still valid.

To test authentication:

Try making the request using Postman or cURL with correct credentials.
If authentication fails, refresh the access token or check API permissions.

Step 6: Review Power Automate Plan and Limits

The HTTP trigger is a premium connector and may not work on free or basic plans.
If your flow suddenly stops working, check if your trial period has expired or if your plan supports HTTP triggers.

To check your plan:

Go to Power Automate > Settings > Billing & Licensing.
Verify whether you have access to premium connectors.
If necessary, upgrade your plan.

Step 7: Monitor API Throttling and Rate Limits

If too many requests are sent in a short time, Power Automate may reject requests due to throttling.
To avoid this, reduce request frequency and implement retry logic.

Example Retry Logic in Postman or Code:

import requests
import time

url = "https://prod-00.westus.logic.azure.com/workflows/{flow-id}/triggers/manual/paths/invoke"
headers = {"Content-Type": "application/json"}
data = {"name": "John Doe", "email": "john.doe@example.com"}

for attempt in range(3):  # Retry up to 3 times
    response = requests.post(url, json=data, headers=headers)
    if response.status_code == 200:
        print("Request successful")
        break
    else:
        print(f"Attempt {attempt + 1}: Failed with status {response.status_code}, retrying...")
        time.sleep(5)  # Wait 5 seconds before retrying

Step 8: Check for Microsoft Service Downtime

If Power Automate services are experiencing delays or outages, the HTTP trigger may fail.
Visit https://status.office.com to check if there are ongoing issues.

Step 9: Verify Firewall and Network Settings

If the HTTP request is blocked by a corporate firewall, VPN, or proxy, it may never reach Power Automate.
To test this, try making the request from:
- A different network (e.g., mobile hotspot).
- A different browser or tool (e.g., Postman).

Step 10: Recreate the HTTP Trigger in Power Automate

If none of the above solutions work, try deleting and re-adding the HTTP trigger in your flow.
Generate a new Trigger URL and update it in your external application or script.