Yahoo! Merchant Checkout API Problems
===

I'm attempting to integrate with Yahoo!'s Checkout API for an existing Merchant account in a Django-based web app. I've already successfully been able to integrate their Catalog API, but for some reason I simply cannot get the Checkout API to work. I've crafted an XML request based on the example in their documentation, but it always simply returns a 10009 Auth Required error. I've confirmed that my partner account does, indeed have the correct authorization, and I just can't figure out why I would be getting this error. I don't believe that it's a malformed request, as I get the exact same result when I copy and paste their example request (changing the API token and such, obviously).

This is what my request looks like (with the store ID and token sanitized):
    
    <ystorews:ystorewsRequest xmlns:ystorews="urn:yahoo:sbs:ystorews">
      <Version>1.0</Version>
      <StoreID>{storeid}</StoreID>
      <SecurityHeader>
            <PartnerStoreContractToken>{token}</PartnerStoreContractToken>
      </SecurityHeader>
      <Verb>create</Verb>
      <ResourceList>
        <CheckoutBasket>
          <ShoppingCart>
            <Item>
              <ID>foo</ID>
              <Quantity>5</Quantity>
            </Item>
          </ShoppingCart>
        </CheckoutBasket>
      </ResourceList>
    </ystorews:ystorewsRequest>

And this is the response that I get back:
    
    <?xml version="1.0" encoding="utf-8"?>
    <ystorewsResponse>
    <ErrorMessages>
    <Error>
    <Code> 10009 </Code>
    <Message> Auth Required </Message>
    </Error>
    </ErrorMessages>
    </ystorewsResponse>

And this is what my Partner API Access looks like:
![Yahoo! Partner API Access][1]


  [1]: http://i.stack.imgur.com/BcCQa.jpg