Unexpected end of MIME multipart stream in web api - asp.net-web-api

Question

Unexpected end of MIME multipart stream. MIME multipart message is not complete error comming when override Stream::GetStream method of MultipartFormDataStreamProvider. I am getting stream in GetStream method and encrypt it and returning it than it gives me this error (Unexpected end of MIME multipart stream). I have done all previous solutions, but doesn't work.
Here is my code:
var Savedfiledata = await Request.Content.ReadAsMultipartAsync(provider).ContinueWith(
(Task<CustomMultipartFormData> readTask) =>
{
CustomMultipartFormData CMF = readTask.Result;// Here Error is comming
// Create response containing information about the stored files.
return CMF.FileData.Select(fileData =>
{
FileInfo info = new FileInfo(fileData.LocalFileName);
ContentDispositionHeaderValue disposition = fileData.Headers.ContentDisposition;
string filename = (disposition != null && disposition.FileName != null) ? disposition.FileName : string.Empty;
CS_FileUpload FileObj = new CS_FileUpload()
{
FileName = filename.Replace("\"", ""),
FileUniqueName = info.Name,
FileSize = (info.Length / 1024),
FilePath = info.DirectoryName,
FileType = info.Extension,
InsertDate = info.LastWriteTimeUtc,
};
DAObj.CS_FileUpload.Add(FileObj);
return FileObj;
}).ToList();
});
public override Stream GetStream(HttpContent filedata, HttpContentHeaders headers)
{
Stream reqStream = filedata.ReadAsStreamAsync().Result;
using (MemoryStream stream = new MemoryStream())
{
reqStream.CopyTo(stream);
MemoryStream getEncBytes = Encrypt(stream, GenerateKey());
return getEncBytes;
}
}