C#

class Program
{
    [System.Runtime.InteropServices.DllImport("winmm.dll", EntryPoint = "mciGetErrorString")]
    public static extern bool mciGetErrorString(int dwError, StringBuilder lpstrBuffer, int uLength);

    [System.Runtime.InteropServices.DllImport("winmm.dll")]
    private static extern int mciSendString(string strCommand, string strReturn, int iReturnLength, IntPtr hwndCallback);

    static void Main(string[] args)
    {
        string Pcommand = "open \"" + "C:\\SomeNonExistantFile.mp3" + "\" type mpegvideo alias MediaFile";
        int err = mciSendString(Pcommand, null, 0, IntPtr.Zero);
        StringBuilder text = new StringBuilder(128, 128);

        mciGetErrorString(err, text, int.MaxValue);
        Console.WriteLine(text);

        Console.WriteLine();
        Console.WriteLine("Press Any Key");
        Console.ReadKey();
    }
}

[System.Runtime.InteropServices.DllImport("winmm.dll")]
private static extern int mciGetErrorString(UInt32 errorCode, StringBuilder buffer, UInt32 iReturnLength);

StringBuilder sb = new StringBuilder(260);
mciGetErrorString(256+37, sb, 260); //256+37 == MCIERR_BAD_TIME_FORMAT
Console.WriteLine(sb.ToString());

Mark Salsbery
Microsoft MVP - Visual C++