为何在部署IIS服务器时无法从Web API获得pdf文件输出？

Question

Web api具有此方法；

public HttpResponseMessage GetReport()
{
     var data = Logic.GetReportAsByteArray(...);

     HttpResponseMessage response = new HttpResponseMessage();
     response.Content = new ByteArrayContent(data);
     response.Content.Headers.ContentType = new MediaTypeHeaderValue("application/pdf");
     response.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment");
     response.Content.Headers.ContentDisposition.FileName = "filename.pdf";
     response.StatusCode = HttpStatusCode.OK;

     return response;
}  

Web客户端通过此方法进行消费；

...

var request = new HttpRequestMessage(...)

HttpClient client = new HttpClient();
var response = await client.SendAsync(request);

var data = await response.Content.ReadAsByteArrayAsync();
return File(data, "application/pdf", "filename.pdf");

...  

当我在本地运行时，我通过Web客户端获得pdf文件作为输出。通过Swagger，我还可以获得文件输出。但是，当我在IIS服务器上进行部署时，我通过Web客户端和Swagger获得了空白的pdf文件，根本没有任何文件，并且响应主体只有下一个文件：

 {
  "Version": {
    "_Major": 1,
    "_Minor": 1,
    "_Build": -1,
    "_Revision": -1
  },
  "Content": {
    "Headers": [
      {
        "Key": "Content-Type",
        "Value": [
          "application/pdf"
        ]
      },
      {
        "Key": "Content-Disposition",
        "Value": [
          "attachment; filename=filename.pdf"
        ]
      }
    ]
  },
  "StatusCode": 200,
  "ReasonPhrase": "OK",
  "Headers": [],
  "RequestMessage": null,
  "IsSuccessStatusCode": true
}