System.Sammlungen.ListDictionaryInternal Fehler

Ich versuche ein Programm erstellen, wo jedes mal, wenn ich eine Textdatei erstellen,wird die Datei komprimiert und melden Sie es .
Es funktioniert für die erste text-Datei, aber wenn ich die zweite bekomme ich diese exception: System.Collections.ListDictionaryInternal

Error:The process cannot access the file 'D:\TemeC#\FilesHomework\FilesHomework\ obj\Debug\New Text Document.txt' because it is being used by another process.

Dies ist mein code:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using System.IO;
using System.IO.Compression;
using System.Security.Permissions;

namespace FilesHomework
{
    class Program
    {

        static void Main(string[] args)
        {

            Run();
        }
        [PermissionSet(SecurityAction.Demand, Name = "FullTrust")]
        public static void Run()
        {

            FileSystemWatcher watcher = new FileSystemWatcher();
            watcher.Path = "D:";
            watcher.NotifyFilter = NotifyFilters.LastAccess | NotifyFilters.LastWrite
           | NotifyFilters.FileName | NotifyFilters.DirectoryName;
            watcher.Filter = "*.txt";
            watcher.Created += new FileSystemEventHandler(OnChanged);
            watcher.EnableRaisingEvents = true;
            Console.WriteLine("Press \'q\' to quit the sample.");
            while (Console.Read() != 'q') ;

        }

        private static void OnChanged(object source, FileSystemEventArgs e)
        {
            try {
                FileInfo FileIn = new FileInfo(e.Name);
                Compress(FileIn);
                //FileStream LogFile = File.Open("LogFile.txt",FileMode.OpenOrCreate,FileAccess.ReadWrite,FileShare.ReadWrite);
                // File.SetAttributes("LogFile.txt", FileAttributes.Normal);
                // StreamWriter sw = new StreamWriter(LogFile);
                string str;

                str = ("The file " + e.Name + " has been deleted at  " + DateTime.Now);
                //byte[] b1 = System.Text.Encoding.UTF8.GetBytes(str);
                // sw.WriteLine(str);
                Console.WriteLine(str);
                File.Delete(e.Name);


                // LogFile.Close();
                //   sw.Close();
            }
            catch(Exception er)
            {
                Console.WriteLine("Error:" + er.Data);
            }


        }
        public static void Compress(FileInfo fileSelected)
        {

            using (FileStream originalFileStream = fileSelected.OpenRead())
            {
                if ((File.GetAttributes(fileSelected.FullName) &
                   FileAttributes.Hidden) != FileAttributes.Hidden & fileSelected.Extension != ".gz")
                {
                    using (FileStream compressedFileStream = File.Create(fileSelected.Name+ ".gz"))
                    {
                        using (GZipStream compressionStream = new GZipStream(compressedFileStream,
                           CompressionMode.Compress))
                        {
                            originalFileStream.CopyTo(compressionStream);


                        }
                    }

                }


            }

        }
    }
}

Was denken Sie ich tun soll?