title: DocuSign API: Trying to move envelopes and getting error
body: <p>relatively new to SO so be easy on me :)</p>
  <p>Anyways, I am using the C# DocuSign API to try and move some envelopes from one folder to another.  I'm getting an &quot;Invalid response type.&quot; exception however, even though the envelopes are actually being moved as expected.  Here is my code - can anyone immediately spot what I'm doing wrong here or how to call this function without getting an exception?</p>
  <pre><code>namespace DocuSign.RetrieveEnvelopes
  {
      public class Program
      {
          private static readonly EnvelopesApi _envelopesApi = new EnvelopesApi();
          private static readonly FoldersApi _foldersApi = new FoldersApi();
          private static readonly FoldersRequest _foldersRequest = new FoldersRequest();
          private static Folder targetFolder;
          private static Folder fromFolder;
  
          private static void Main(string[] args)
          {
              try
              {
                  DocuSignUtils.ConfigureApiClient();
                  Config.AccountId = DocuSignUtils.Authenticate();
  
                  var folders = _foldersApi.List(Config.AccountId);
                  _foldersRequest.EnvelopeIds = new List&lt;string&gt;();
  
                  foreach (var foldr in folders.Folders)
                  {
                      if (foldr.Name == &quot;Completed&quot;) { targetFolder = foldr; }
                      else if (foldr.Name == &quot;Sent Items&quot;) { fromFolder = foldr; }
                  }
  
                  var envelops = _foldersApi.ListItems(Config.AccountId, fromFolder.FolderId);
  
                  foreach (FolderItem fItem in envelops.FolderItems)
                  {
                      Envelope eItem = _envelopesApi.GetEnvelope(Config.AccountId, fItem.EnvelopeId);
  
                      if (eItem.Status == &quot;completed&quot;)
                      {
                          _foldersRequest.EnvelopeIds.Add(eItem.EnvelopeId);
  
                          var docItem = _envelopesApi.GetDocument(Config.AccountId, eItem.EnvelopeId, &quot;combined&quot;);
                          var fStream = File.Create(&quot;C:\\Temp\\data\\&quot; + eItem.EmailSubject.ToString() + &quot;.pdf&quot;);
                          docItem.Seek(0, SeekOrigin.Begin);
                          docItem.CopyTo(fStream);
                          fStream.Close();
  
                      }
                  }
  
  
                  if (_foldersRequest.EnvelopeIds.Count &gt;= 1)
                  {
                      FoldersResponse fResponse = _foldersApi.MoveEnvelopes(Config.AccountId, targetFolder.FolderId, _foldersRequest);
                  }
                  
              catch (Exception ex)
              {
                  RetrieveEnvelopsErrorHandler.LogException(ex);
              }
          }
  }
  </code></pre>
  <p>Note: _foldersApi is a FoldersAPI object and _foldersRequest is a FoldersRequest object with envelope ids of the envelopes I'd like to move.  Also, I tried just calling this function directly without assigning the return value to a FoldersResponse var but it gave the same error.</p>
  <p>Stack Trace:</p>
  <pre><code>&quot; at DocuSign.eSign.Client.ApiClient.Deserialize(Byte[] content, Type type, IList`1 headers)\r\n   at DocuSign.eSign.Api.FoldersApi.MoveEnvelopesWithHttpInfo(String accountId, String folderId, FoldersRequest foldersRequest)\r\n   at DocuSign.eSign.Api.FoldersApi.MoveEnvelopes(String accountId, String folderId, FoldersRequest foldersRequest)\r\n   at DocuSign.RetrieveEnvelopes.Program.Main(String[] args) in C:\\DocuSign\\DocuSign.RetrieveEnvelopes\\Program.cs:line 73&quot;
  </code></pre>