C# “Bad Data” exception when decrypting encrypted file

Question

Hey I\'m very new to encryption and decryption, or even the c# language to be honest. Basically, I have a tcp chat server that \"saves\" logs and encrypts the text file. Thi

Answer 1

  objCryptStream.CopyTo(stream);

Worked for me, complete code is

 public static string DecryptString(string encriptedText, string key)
   {

       try
       {


           //Convert the text into bytest
           byte[] ecriptedBytes = System.Convert.FromBase64String(encriptedText);

           // Create a memory stream to the passed buffer
           MemoryStream objMemStream = new MemoryStream(ecriptedBytes);

           //Set the legal keys and initialization verctors
           objCrptoService.Key = GetLegalsecretKey(key);
           objCrptoService.IV = GetLegalIV();

           // Create a CryptoStream using the memory stream and the cryptographic service provider  version
           // of the Data Encryption stanadard algorithm key
           CryptoStream objCryptStream = new CryptoStream(objMemStream, objCrptoService.CreateDecryptor(), CryptoStreamMode.Read);

           // Create a StreamReader for reading the stream.
           //StreamReader objstreamReader = new StreamReader(objCryptStream);
           MemoryStream stream = new MemoryStream();
           objCryptStream.CopyTo(stream);
           stream.Position = 0;
           StreamReader R = new StreamReader(stream);
           string outputText = R.ReadToEnd();

           // Close the streams.
           R.Close();
           objCryptStream.Close();
           objMemStream.Close();

           return outputText;
       }
       catch (Exception exc)
       {
           return "";
       }
   }