I have to submit a form like as follows: 

    <input type="file" name="jpgFile">

I can't seem to find any instructions on sending this in URLExecute. If I specify the file name as the parameter it fails. If I try `Import[filename, "JPG"]` of the image it also fails as invalid. 

I thought his might work, but I get an error `"Iteration limit of 4096 exceeded"`. This suggests it might be working as test file is 451,107 bytes.

    URLExecute[ url,
     "Method" -> "POST",
     "Headers" -> {
       "Accept" -> "application/json; charset=UTF-8"
       },
      {
       {"jpgFile", "file"} -> "test.jpg"
      }
     ]