As the title says, I am getting:

Invalid length for a Base-64 char array.

I have read about this problem on here and it seems that the suggestion is to store ViewState in SQL if it is large. I am using a wizard with a good deal of data collection so chances are my ViewSate is large. But, before I turn to the "store-in-DB" solution, maybe somebody can take a look and tell me if I have other options?

I construct the email for delivery using the below method:

public void SendEmailAddressVerificationEmail(string userName, string to)
        {
            string msg = "Please click on the link below or paste it into a browser to verify your email account.<BR><BR>" +
                            "<a href=\"" + _configuration.RootURL + "Accounts/VerifyEmail.aspx?a=" +
                            userName.Encrypt("verify") + "\">" +
                            _configuration.RootURL + "Accounts/VerifyEmail.aspx?a=" +
                            userName.Encrypt("verify") + "</a>";

            SendEmail(to, "", "", "Account created! Email verification required.", msg);
        }

The Encrypt method looks like this:

public static string Encrypt(string clearText, string Password)
        {

            byte[] clearBytes = System.Text.Encoding.Unicode.GetBytes(clearText);

            PasswordDeriveBytes pdb = new PasswordDeriveBytes(Password, new byte[] { 0x49, 0x76, 0x61, 0x6e, 0x20, 0x4d, 0x65, 0x64, 0x76, 0x65, 0x64, 0x65, 0x76 });


            byte[] encryptedData = Encrypt(clearBytes, pdb.GetBytes(32), pdb.GetBytes(16));

            return Convert.ToBase64String(encryptedData);
        }

On the receiving end, the VerifyEmail.aspx.cs page has the line:

 string username = Cryptography.Decrypt(_webContext.UserNameToVerify, "verify");

And the decrypt method looks like:

 public static string Decrypt(string cipherText, string password)
        {

            **// THE ERROR IS THROWN HERE!!**
            byte[] cipherBytes = Convert.FromBase64String(cipherText);

Can this error be remedied with a code fix or must I store ViewState in the database?

Thanks in advance.