Compatibility level and writing *.txt files

I am using a script to create a text file in “my documents” folder. It works perfectly while testing it in the Editor, but when I build and run the standalone it doesn’t work anymore.

Facts: 1) I use Unity free 2) API compatibility level in player preferences: .NET 2.0 (not subset) 3) There are no compilation errors or warnings

The funny thing is that my game also has scripts that use: System.IO; System.Reflection; and System.Runtime.Serialization; to create “save game files” and it works just fine.

What could be possibly going wrong? Here is the script to create *.txt files thank you in advance:

 using System;

using System.IO; using System.Text;

public class WriteTextFile { static string mydocpath; static string[] txtList; static StringBuilder sb = new StringBuilder ();

 public static void WriteFile ()
 {
     mydocpath = Environment.GetFolderPath (Environment.SpecialFolder.MyDocuments);
     txtList = Directory.GetFiles (mydocpath, "*.txt");        

     foreach (string txtName in txtList) {
         using (StreamReader sr = new StreamReader(txtName, Encoding.GetEncoding(1252))) {
             sb.AppendLine (txtName.ToString ());
             sb.AppendLine ("= = = = = =");
             sb.Append (sr.ReadToEnd ());
             sb.AppendLine ();
             sb.AppendLine ();
         }
     }   

     using (StreamWriter outfile = new StreamWriter (mydocpath + @"\AllTxtFiles.txt", false, Encoding.GetEncoding(1252))) {

         string temp = sb.ToString ();
         outfile.Write (temp);
     }
 }

}