using System;
using System.IO;
using System.Reflection;

namespace ConsoleApplication1 {
    #region Presentation
    class Program {
        static void Main(string[] args) {
            bool exitProgram = false;

            do {
                try {
                    Console.WriteLine("Enter the name of a counter and press ENTER:");
                    string fileName = Console.ReadLine();
                    var incrementor = new Incrementor((new FileNameGenerator()).GenerateFileName(fileName));
                    var result = incrementor.PerformIncrement();
                    Console.WriteLine("Value of counter: {0}", result.PreviousValue);
                    exitProgram = true;
                    Console.WriteLine("Press enter for exit.");
                    Console.ReadLine();
                } catch (Exception ex) {
                    var myFriend = new FriendlyMessageGenerator();
                    var msg = myFriend.GetFriendly(ex);
                    Console.WriteLine("Friendly message: {0}", msg.Message);
                    Console.WriteLine("Error details: {0}", msg.Details);
                    
                    Console.WriteLine("Would you like to try again?");
                    if (Console.ReadLine().Equals("n", StringComparison.OrdinalIgnoreCase)) {
                        exitProgram = true;
                    }
                }
            } while (!exitProgram);

        }
    }
    #endregion

    #region SharedApplicationComponent
    public class FileNameGenerator {
        private const string EXTENSION = ".txt";
        public string GenerateFileName(string counterName) {
            return Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location) + Path.DirectorySeparatorChar + counterName + EXTENSION;
        }
    }
    public class FriendlyMessageGenerator {
        public FriendlyMessage GetFriendly(Exception ex) {
            string message;
            if (ex is IncrementorException) {
                message = (ex as IncrementorException).Message;
            } else {
                message = "Unexpected error has been happened during executing the task. Please, see the details.";
            }
            return new FriendlyMessage(message, ex);
        }
    }
    public class FriendlyMessage {
        public FriendlyMessage(string message, Exception exception) {
            Message = message;
            Details = exception;
        }
        public string Message { get; private set; }
        public Exception Details { get; private set; }
    }
    #endregion

    #region BusinessLogicComponent
    public class Incrementor {
        private string _counterFileName;
        private const int STARTUP_NUMBER = 0;
        
        public Incrementor(string counterFileName) {
            _counterFileName = counterFileName;
        }
        public Result PerformIncrement() {
            CreateFileIfItDoesNotExist();
            var oldValue = ReadCurrentValue();
            var newValue = oldValue + 1;
            WriteNewValue(newValue);
            return new Result(oldValue, newValue);
        }
        private int ReadCurrentValue() {
            try {
                return int.Parse(File.ReadAllText(_counterFileName));
            } catch (Exception ex) {
                throw new IncrementorException("Error during reading current value", ex);
            }
        }
        private void WriteNewValue(int newValue) {
            try {
                File.WriteAllText(_counterFileName, newValue.ToString());
            } catch (Exception ex) {
                throw new IncrementorException("Error during writing new value", ex);
            }
        }
        private void CreateFileIfItDoesNotExist() {
            if (!File.Exists(_counterFileName)) {
                try {
                    File.Create(_counterFileName).Close();
                    File.WriteAllText(_counterFileName, STARTUP_NUMBER.ToString());
                } catch (Exception ex) {
                    throw new IncrementorException("Error during file creating", ex);
                }
            }
        }
    }
    public class IncrementorException : Exception {
        public IncrementorException() { }
        public IncrementorException(string message) : base(message) { }
        public IncrementorException(string message, Exception inner) : base(message, inner) { }
        protected IncrementorException(
          System.Runtime.Serialization.SerializationInfo info,
          System.Runtime.Serialization.StreamingContext context)
            : base(info, context) { }
    }
    public class Result {
        public Result(int previousValue, int newValue) {
            PreviousValue = previousValue;
            NewValue = newValue;
        }
        public int PreviousValue { get; private set; }
        public int NewValue { get; private set; }
    }
    #endregion
}

        private void WriteNewValue(int newValue) {
            try {
                File.WriteAllText(_counterFileName, newValue.ToString());
            } catch (Exception ex) {
                throw new IncrementorException("Error during writing new value", ex);
            }
        }

M>Файл вполне доступен, только видимо слишком большой для программы. Ничего не "разжёвывается".

---------------------------
Open
---------------------------
File C:\#$# does not exist.

Verify that the correct file name was given.
---------------------------
OK
---------------------------

---------------------------
Open
---------------------------
8888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888
The above file name is invalid.
---------------------------
OK
---------------------------

---------------------------
Paint.NET
---------------------------
An I/O error occurred when writing to the file.
---------------------------
OK
---------------------------

---------------------------
Paint.NET
---------------------------
There was an error reading the file from the media.
---------------------------
OK
---------------------------

0K>using System;
0K>using System.IO;

0K>namespace ConsoleApplication1
0K>{
0K>    class Program
0K>    {
0K>        static void Main(string[] args)
0K>        {
0K>01            Console.WriteLine("Введите имя счетчика и нажмите ENTER:");
            
0K>02            string fileName = Console.ReadLine();

0K>            // Если файла не существует -- нужно создать.
0K>            // Может не быть доступа к файлу
0K>            // Имя счетчика может быть некорректным -- с этим что-то нужно сделать
0K>03            string text = File.ReadAllText(fileName);

0K>04            int count = int.Parse(text);

0K>05            Console.WriteLine("Значение счетчика: ", count);

0K>06            count++;

0K>            // Может быть запрещена запись в файл
0K>07            File.WriteAllText(fileName, count.ToString());
0K>        }
0K>    }
0K>}
0K>

Console.WriteLine("Введите имя счетчика и нажмите ENTER:");
string fileName = Console.ReadLine();
string text = "";
try
{
    text = File.ReadAllText(fileName);
}
catch (NotFoundException e)
{
    text = "-1"
}

int count = 0;
try
{
    count = int.Parse(text);
}
catch (FormatException e)
{
    count = -1;
}

static void Main(string[] args)
{
    Console.WriteLine("Введите имя счетчика и нажмите ENTER:");
    
    string fileName = Console.ReadLine();

    string text = "";
    try
    {
        text = File.ReadAllText(fileName);
        Console.WriteLine("Счётчик '{0}' найден.", text);
    }
    catch (NotFoundException e)
    {
        text = "-1"
        Console.WriteLine("Счётчик '{0}' не найден и будет создан.", text);
    }

    int count = 0;
    try
    {
        count = int.Parse(text);
    }
    catch (FormatException e)
    {
        count = -1;
    }

    Console.WriteLine("Значение счетчика: ", count);

    count++;

    try
    {
        File.WriteAllText(fileName, count.ToString());
    }
    catch (SecurityException e)
    {
        Console.WriteLine("Счётчик '{0}' обновить не удалось.", text);
        throw;
    }
}

static void Main(string[] args)
{
    Console.WriteLine("Введите имя счетчика и нажмите ENTER:");
    
    string fileName = Console.ReadLine();

    string text = "";
    try
    {
        text = File.ReadAllText(fileName);
    }
    catch (NotFoundException e)
    {
        text = "-1"
    }

    int count = 0;
    try
    {
        count = int.Parse(text);
    }
    catch (FormatException e)
    {
        count = -1;
    }

    Console.WriteLine("Значение счетчика: ", count);

    count++;

    File.WriteAllText(fileName, count.ToString());
}

A>int count = 0;
A>try
A>{
A>    count = int.Parse(text);
A>}
A>catch (FormatException e)
A>{
A>    count = -1;
A>}
A>

int count = 0;
if(!int.TryParse(text, out count))
  count = -1;

# It hides bugs

# Handling all exceptions without exception-specific handling logic will leave the application in an unknown state.

# It circumvents higher-level exception handling.

A higher-level exception handler may know exactly what to do with a certain type of exception; possibly much better than your code. By using catch(Exception) you circumvent that and end up with the above--the application may be in a unknown state.

                    string fileName = Console.ReadLine();
                    var incrementor = new Incrementor((new FileNameGenerator()).GenerateFileName(fileName));
                    try {
                        var result = incrementor.PerformIncrement();
                    } catch (FileNotFoundException ex)  {
                        Console.WriteLine("The file [{0}] was not found", fileName);
                    }