What mimeType shall I set when uploading files by HttpClient?

Question

My code is below. I found some types of files can't be uploaded correctly with this code, such as the 7-zip compressed files. Also, there are some uploaded correctly.

The uploaded file size is smaller than the whole file when this problem occurred. And if I changed the mime type, the uploaded file size will be changed.

So I guess it's the problem of the mime type. What mime type shall I set to upload files of different types? Shall I set it separately for different file types, or set a general type for all of the file types?

public void DoUpload(String url, String filename) {
        HttpClient httpclient = new DefaultHttpClient();
        httpclient.getParams().setParameter(CoreProtocolPNames.PROTOCOL_VERSION, HttpVersion.HTTP_1_1);

        HttpPost httppost = new HttpPost(url);
        File file = new File(filename);

        MultipartEntity mpEntity = new MultipartEntity();
        ContentBody cbFile = new FileBody(file, "application/x-normal");
        mpEntity.addPart("userfile", cbFile);

        httppost.setEntity(mpEntity);
        //writeLog("executing request " + httppost.getRequestLine());

        initTime = System.nanoTime();
        try {
                HttpResponse response = httpclient.execute(httppost);
                HttpEntity resEntity = response.getEntity();

                //writeLog(response.getStatusLine().toString());
                if (resEntity != null) {
                  //writeLog(EntityUtils.toString(resEntity));
                }
                if (resEntity != null) {
                  resEntity.consumeContent();
                }
                writeLog(String.format("Upload: [%s] Success!!! ...upload time: %d ms", 
                            file.toString(), (System.nanoTime()-initTime)/1000000));
        }
        catch (Exception e) {
            writeLog(String.format("Upload: [%s] FAILED!!! error: %s", file.toString(), e.toString()));
        }
        httpclient.getConnectionManager().shutdown();
}