When i attempt to decrypto my string i get the following error:

System.Web.Services.Protocols.SoapException: Server was unable to process request. ---> System.Security.Cryptography.CryptographicException: Length of the data to decrypt is invalid.

at System.Security.Cryptography.RijndaelManagedTransform.TransformFinalBlock(Byte[] inputBuffer, Int32 inputOffset, Int32 inputCount)

The code i try is:

 System.IO.MemoryStream ms = new System.IO.MemoryStream(encryptedcryptData.Bytes, 0, encryptedcryptData.Bytes.Length);
            byte[] b = new byte[encryptedcryptData.Bytes.Length - 1 + 1];

            ValidateKeyAndIv(false);
            CryptoStream cs = new CryptoStream(ms, _crypto.CreateDecryptor(), CryptoStreamMode.Read);

            try
            {
                cs.Read(b, 0, encryptedcryptData.Bytes.Length - 1);
            }
            catch (CryptographicException ex)
            {
                throw new CryptographicException("Unable to decrypt cryptData. The provided key may be invalid.", ex);
            }
            finally
            {
                cs.Close();
            }
            return new cryptData(b);

How can i get rid of this error. Thank sin advance...

try  this link... Hope this can solve your problem...

http://forums.asp.net/t/1491121.aspx

 

For some encrypt/decrypt routines, please look at CommonEncrypt.cs in the CommonCS project in the CommonData solution at http://commondata.codeplex.com/Thread/View.aspx?ThreadId=26395

These routines will encrypt/decrypt and come with unit tests to validate them.