MultipartUtility Android Extra bytes

Question

Can anybody tell me what I'm doing wrong in the code below? I'm sending part of the file from Android/Java to Asp.Net C# Web API.

the array of bytes received on the server side has two extra bytes that are breaking the checksum of the file.

I'm using the MultipartUtility class posted here: simple HttpURLConnection POST file multipart/form-data from android to google blobstore

here is my code to send the array of bytes to the server:

 public void addFilePart(String fieldName, byte[] stream) throws IOException {
    String fileName = "file";
    writer.append("--" + boundary).append(LINE_FEED);
    writer.append("Content-Disposition: form-data; name=\"" + fieldName + "\"; filename=\"" + fileName + "\"").append(LINE_FEED);
    writer.append("Content-Type: " + URLConnection.guessContentTypeFromName(fileName)).append(LINE_FEED);
    writer.append("Content-Transfer-Encoding: binary").append(LINE_FEED);
    writer.append(LINE_FEED);
    writer.flush();

    outputStream.write(stream);
    outputStream.flush();

    writer.append(LINE_FEED);
    writer.flush();
}
public List<String> finish() throws IOException {
    List<String> response = new ArrayList<String>();
    writer.append(LINE_FEED);
    writer.flush();
    writer.append("--" + boundary + "--");
    writer.append(LINE_FEED);
    writer.flush();
    writer.close();

    // checks server's status code first
    int status = httpConn.getResponseCode();
    if (status == HttpURLConnection.HTTP_OK) {
        BufferedReader reader = new BufferedReader(new InputStreamReader(
                httpConn.getInputStream()));
        String line = null;
        while ((line = reader.readLine()) != null) {
            response.add(line);
        }
        reader.close();
        httpConn.disconnect();
    } else {
        throw new IOException("Server returned non-OK status: " + status);
    }
    return response;
}

I can post the whole class if needed, it's really the link above.

Thank you for your help. Sean