Getting Signature mismatch error when browsing the Amazon MWS API's request URL

I want to retrieve orders from : with Action = ListOrders

Here is the string that I had created as string to be signed :





Am I missing something here?

I’m trying to setup a similar scenario, looking for some leads.

Can you please share a working setup if you have one in place.

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It seems like you are on the right track, but there might be a couple of issues with the string you provided. Here’s a breakdown of the steps you need to follow to correctly retrieve orders from the specified date using the MWS API:

  1. Ensure you have the necessary permissions and access keys for MWS API.
  2. Construct the string to be signed by following these guidelines:
  • Start with the HTTP method, which in this case is “GET.”
  • Add the domain name, “”
  • Include the API endpoint for orders, which is “/Orders/2022-09-01”.
  • Add the query parameters in alphabetical order, excluding any empty parameters. Based on your example, the correct order should be:
    • Action=ListOrders
    • AWSAccessKeyId=myaccesskeyid
    • MarketplaceId.Id.1=ATVPDKIKX0DER
    • SignatureMethod=HmacSHA256
    • SignatureVersion=2
    • Timestamp=2022-06-6T01%3A10%3A27.607Z
    • Version=2022-09-01
  1. Once you have the string to be signed, you need to sign it using your access key secret and the HMAC-SHA256 algorithm.
  2. Compare the resulting signature with the “Signature” parameter you included in the original string. Ensure that the signatures match.

If you followed these steps correctly and the signature is valid, you should be able to retrieve the orders from the specified date using the MWS API. Double-check the correctness of the parameters, including your access key ID, marketplace ID, and the date format.

If you continue to encounter issues, it’s recommended to consult the Amazon MWS documentation or reach out to the Amazon MWS support team for further assistance.

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