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Receiving Error for Base-64 Char Array

I had a question here about encrypting data (in a basic way). Anyway it was all working fine, however I decided to have my XML data encrypted so that I could have it slightly more secure, then using a Recovery form I could view what the pin is during development. However I get the following error:
Invalid length for a Base-64 char array.

It happens when the following code is called to get all the IDs, Pins, DOBs etc:
EncDecrypt decrypt = new EncDecrypt(key, iv);
XmlDocument myDoc = new XmlDocument();
myDoc.Load(@"C:\Projects\myXML.xml");

XmlNodeList list = myDoc.SelectNodes("//Accounts/Account");
XmlNode node;
for (int i = 0; i < list.Count; i++)
{
node = list[i];
string id = node.Attributes.GetNamedItem("ID").Value.ToString();
string pin = node.Attributes.GetNamedItem("PIN").Value.ToString();
string dob = node.Attributes.GetNamedItem("DOB").Value.ToString();

string decryptedPin = decrypt.Decrypt(pin); // The call to decrypt the string PIN
}

Then it enters the encryption class:

public string Decrypt(string text)
{
byte[] input = Convert.FromBase64String(text); // Where the error occurs
byte[] output = Transform(input,
m_des.CreateDecryptor(m_key, m_iv));
return m_utf8.GetString(output);
}

I'm rather stuck on how to fix this. I am able to encrypt/decrypt in my other forms but this one keeps throwing that error. Can anybody shed any light on it for me?

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angus_young_acdc

ASKER

I put a messagebox in to check, and the following values appear. These are correct as they are what are stored in my XML file as the encrypted password.

gtPiPkzuAgc
oxOqxV1UqC4=
APoBMHbBAOc
8FC7r4hmw5k

I can easily decrypt the pins if it is just searching for one of them, but when returning (and decrypting) all of the users in my XML it kicks up a fuss.

I have even tried creating a new data object to hold the info, adding each of them to a list, and then doing a foreach. For example:

List<CustomerData> custData = new List<CustomerData>();
            EncDecrypt decrypt = new EncDecrypt(key, iv);
            XmlDocument myDoc = new XmlDocument();
            myDoc.Load(@"C:\Projects\Accounts.xml");
         
 
            XmlNodeList list = myDoc.SelectNodes("//Accounts/Account");
            XmlNode node;
            for (int i = 0; i < list.Count; i++)
            {
                node = list[i];
                string id = node.Attributes.GetNamedItem("ID").Value.ToString();
                string pin = node.Attributes.GetNamedItem("PIN").Value.ToString();
                string dob = node.Attributes.GetNamedItem("DOB").Value.ToString();
 
                CustomerData data = new CustomerData(id, dob, pin); // Takes 3 strings
                custData.Add(data);
            }
            foreach (CustomerData obj in custData)
            {
                string pass = decrypt.Decrypt(obj.PIN);
            }

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angus_young_acdc

ASKER

Ugh can't believe it, just figured out what it was by running a test whereby I changed the pin to one that I already know the encrypted string for, turned out when I copy/pasted them into the XML I missed the "=" at the end.

So although reading the XML was correct (it output exactly what was there) the actual XML itself was incorrect, so outputting to console etc couldn't help. Was only able to spot that by what I mentioned.