Encoding not detected

[ilCosmico]

The encoding for the the following file is not detected: https://onedrive.live.com/redir?resid=DBC75114109D3C7E!416&authkey=!AAaNrJIJijrzPCo&ithint=file%2czip

But Visual Studio detect it:

Here following my code snippet:

public static Encoding GetEncodingCharDet(string filename)
{

    Encoding enc = null;

    byte[] buf = new byte[4096];

    UniversalDetector detector = new UniversalDetector();

    using (FileStream fs = File.OpenRead(filename))
    {

        int nread;
        while ((nread = fs.Read(buf, 0, buf.Length)) > 0)
        {
            detector.HandleData(buf);
        }

        detector.DataEnd();

        String encoding = detector.DetectedCharsetName;
        if (encoding != null)
        {            
            enc = System.Text.Encoding.GetEncoding(encoding);
        }
        else
        {
            //Not Detected!
        }
    }

    // (5)
    detector.Reset();
    return enc;
}

Is it a bug or something wrong in my code?

[superstrom]

It's a bug. The detector currently seems to return null for everything. I only recently resurrected this code when Google Code closed down, after having sat stagnant for several years.