new System.Threading.Thread(() => { System.IO.Directory.GetFiles(textBox1.Text, "*.mp3").ToList<string>() .ForEach(f => { try { string filename = new System.Text.RegularExpressions.Regex(@"(^[\d\.\s]{1,})", System.Text.RegularExpressions.RegexOptions.None).Replace(System.IO.Path.GetFileName(f), "").Trim(); System.IO.File.Move(f, System.IO.Path.GetDirectoryName(f) + @"\" + filename); } catch { } }); }).Start();