C# consoleapplication throwing ioexception

The process cannot access F:\MyService.InstallLogI because it is being used by another process.

class Program
    {
        static FileSystemWatcher watcher;
        static void Main(string[] args)
        {
            var drives = DriveInfo.GetDrives();
            
            foreach (var drive in drives)
            {
                if (drive.DriveType == DriveType.Removable)
                {
                    Console.WriteLine(drive.Name);
                    watch(drive.Name);
                }
            }

        }
        static void watch(String path)
        {
            
            watcher = new FileSystemWatcher();

            watcher.Path = path;//assigning path to be watched
            watcher.EnableRaisingEvents = true;//make sure watcher will raise event in case of change in folder.
            watcher.IncludeSubdirectories = true;//make sure watcher will look into subfolders as well.
            watcher.Filter = "*.*"; //watcher should monitor all types of file.

            watcher.Created += watcher_Created; //register event to be called when a file is created in specified path
            watcher.Changed += watcher_Changed;//register event to be called when a file is updated in specified path
            watcher.Deleted += watcher_Deleted;//register event to be called when a file is deleted in specified path

           // watcher.Created += new FileSystemEventHandler(watcher_Changed);


            while (true) ;//run infinite loop so program doesn't terminate untill we force it.
        }

        static void watcher_Deleted(object sender, FileSystemEventArgs e)
        {
            Console.WriteLine("File : " + e.FullPath + " is deleted.");
        }

        static void watcher_Changed(object sender, FileSystemEventArgs e)
        {
            Console.WriteLine("File : " + e.FullPath + " is updated.");

            watcher.EnableRaisingEvents = false;

            try
            {
                if (!string.IsNullOrEmpty(e.FullPath))
                {

                    FileStream fs = new FileStream(e.FullPath, FileMode.Open, FileAccess.Read);
                    byte[] filebytes = new byte[fs.Length];
                    fs.Read(filebytes, 0, Convert.ToInt32(fs.Length));
                    string encodedData = Convert.ToBase64String(filebytes, Base64FormattingOptions.InsertLineBreaks);
                    Console.WriteLine(encodedData);

                    // File.WriteAllText(e.FullPath, encodedData);


                }

              }
            catch (Exception excep)
            {
                Console.WriteLine(excep.Message.ToString());
                //Thread.Sleep(100);
            }


            //watcher.EnableRaisingEvents = true;
        }

        static void watcher_Created(object sender, FileSystemEventArgs e)
        {
            Console.WriteLine("File : " + e.FullPath + " is created.");
           // System.Windows.Forms.Clipboard.Clear();

        }
 
    }