title: Add Product Variant - 404 Error
body: <p>I am developing a VB.NET application to interact with our new Shopify store. I am in the process of automating product additions/updates/removal based on data in our Oracle database.</p>
  
  <p>Basically the application creates a new Shopify part for a pattern, then creates product variants for each sku in that pattern. It does this by POSTing and PUTing requests using the <code>HttpWebRequest</code> class. This was working great through yesterday afternoon, now today for some reason it's failing on the product variant creation/update with a 404 - Not Found error code.</p>
  
  <p>The product add request JSON is below. This works perfectly, it creates the part on Shopify which I can then see through the admin panel. This is POSTed to the URL "<a href="https://key:password@bath-and-window-direct.myshopify.com/admin/products.json" rel="nofollow">https://key:password@bath-and-window-direct.myshopify.com/admin/products.json</a>" (where key and password are replaced with our credentials)</p>
  
  <pre><code>{
      "product": {
          "id": 0,
          "body_html": "A classic combination of embroidery and cut work form the flowing border, creating your own seaside retreat. ",
          "title": "Seabreeze Sand",
          "vendor": "SKL",
          "product_type": "",
          "published_scope": "global",
          "tags": "J71227",
          "variants": null,
          "options": null,
          "images": [{
              "id": 0,
              "product_id": 0,
              "position": 1,
              "src": "http:\/\/i320.photobucket.com\/albums\/nn353\/fkhphoto\/J71227main.jpg",
              "variant_ids": null
          }],
          "image": null
      }
  }
  </code></pre>
  
  <p>This is the JSON reply I'm receiving after this call, and I can also see the part added in the Shopify admin panel:</p>
  
  <pre><code>{
      "product": {
          "id": 7874734983,
          "title": "Seabreeze Sand",
          "body_html": "A classic combination of embroidery and cut work form the flowing border, creating your own seaside retreat. ",
          "vendor": "SKL",
          "product_type": "",
          "created_at": "2016-07-14T10:43:56-04:00",
          "handle": "seabreeze-sand",
          "updated_at": "2016-07-14T10:43:56-04:00",
          "published_at": "2016-07-14T10:43:56-04:00",
          "template_suffix": null,
          "published_scope": "global",
          "tags": "J71227",
          "variants": [{
              "id": 24925005383,
              "product_id": 7874734983,
              "title": "Default Title",
              "price": "0.00",
              "sku": "",
              "position": 1,
              "grams": 0,
              "inventory_policy": "deny",
              "compare_at_price": null,
              "fulfillment_service": "manual",
              "inventory_management": null,
              "option1": "Default Title",
              "option2": null,
              "option3": null,
              "created_at": "2016-07-14T10:43:56-04:00",
              "updated_at": "2016-07-14T10:43:56-04:00",
              "taxable": true,
              "barcode": null,
              "image_id": null,
              "inventory_quantity": 1,
              "weight": 0.0,
              "weight_unit": "lb",
              "old_inventory_quantity": 1,
              "requires_shipping": true
          }],
          "options": [{
              "id": 9404426823,
              "product_id": 7874734983,
              "name": "Title",
              "position": 1,
              "values": ["Default Title"]
          }],
          "images": [{
              "id": 16242879303,
              "product_id": 7874734983,
              "position": 1,
              "created_at": "2016-07-14T10:43:56-04:00",
              "updated_at": "2016-07-14T10:43:56-04:00",
              "src": "https://cdn.shopify.com/s/files/1/1363/2407/products/J71227main.jpg?v=1468507436",
              "variant_ids": []
          }],
          "image": {
              "id": 16242879303,
              "product_id": 7874734983,
              "position": 1,
              "created_at": "2016-07-14T10:43:56-04:00",
              "updated_at": "2016-07-14T10:43:56-04:00",
              "src": "https://cdn.shopify.com/s/files/1/1363/2407/products/J71227main.jpg?v=1468507436",
              "variant_ids": []
          }
      }
  }
  </code></pre>
  
  <p>Immediately after that, I'm POSTing the following JSON to add a product variant to this newly created part, to the URL "<a href="https://key:password@bath-and-window-direct.myshopify.com/admin/products/7874734983/variants.json" rel="nofollow">https://key:password@bath-and-window-direct.myshopify.com/admin/products/7874734983/variants.json</a>". This is the call that returns a 404 - Not Found error through the <code>HttpWebRequest</code> class.</p>
  
  <pre><code>{
      "variant": {
          "id": 0,
          "product_id": 7874734983,
          "title": "Seabreeze Tier Curtain in Sand",
          "price": "11.99",
          "sku": "J7122700013V09",
          "compare_at_price": "0.00",
          "position": 0,
          "grams": 0,
          "option1": "57X13 ROD POCKET VAL",
          "option2": null,
          "option3": null,
          "taxable": true,
          "barcode": "036326422417",
          "weight": 0,
          "weight_unit": "lb",
          "inventory_quantity": 550,
          "old_inventory_quantity": 550,
          "requires_shipping": true,
          "image_id": null,
          "metafields": [{
              "id": 0,
              "key": "point1",
              "value": "57 x 13 Valance",
              "value_type": "string",
              "namespace": "J7122700013V09"
          },
          {
              "id": 0,
              "key": "point2",
              "value": "To achieve the look in the photo, use one valance and one tier pair.",
              "value_type": "string",
              "namespace": "J7122700013V09"
          },
          {
              "id": 0,
              "key": "point3",
              "value": "Feels like you are in your own beach cottage.",
              "value_type": "string",
              "namespace": "J7122700013V09"
          },
          {
              "id": 0,
              "key": "point4",
              "value": "100% Polyester.",
              "value_type": "string",
              "namespace": "J7122700013V09"
          },
          {
              "id": 0,
              "key": "point5",
              "value": " ",
              "value_type": "string",
              "namespace": "J7122700013V09"
          }]
      }
  }
  </code></pre>
  
  <p>What am I doing wrong? The URLs, when copied into a web browser, work perfectly fine...I can see all the JSON of the current data. But when attempting to add the variant, I'm getting the 404.</p>