错误的PKCS7填充错误：Xamarin中无效的长度201形式为PCLCrypto

Question

每当我尝试从升级的移动应用程序解密数据时，都会收到此错误。

但是，当我卸载应用程序并重新安装时，加密和解密就可以完美地工作。

我正在使用以下PCLCrypo代码进行加密和解密。

public static class CryptoUtilities
    {
        const int IVSize = 16;

        public static byte[] GetAES256KeyMaterial()
        {
            return WinRTCrypto.CryptographicBuffer.GenerateRandom(32);
        }

        public static byte[] Get256BitSalt()
        {
            return WinRTCrypto.CryptographicBuffer.GenerateRandom(32);
        }

        public static byte[] Encrypt(byte[] plainText, byte[] keyMaterial)
        {
            var provider = WinRTCrypto.SymmetricKeyAlgorithmProvider.OpenAlgorithm(SymmetricAlgorithm.AesCbcPkcs7);

            var key = provider.CreateSymmetricKey(keyMaterial);
            var IV = WinRTCrypto.CryptographicBuffer.GenerateRandom(IVSize);   // random initialization vector

            var cipher = WinRTCrypto.CryptographicEngine.Encrypt(key, plainText, IV);

            var cipherText = new byte[IV.Length + cipher.Length];

            IV.CopyTo(cipherText, 0);
            cipher.CopyTo(cipherText, IV.Length);

            return cipherText;
        }

        public static byte[] Decrypt(byte[] cipherText, byte[] keyMaterial)
        {
            var provider = WinRTCrypto.SymmetricKeyAlgorithmProvider.OpenAlgorithm(SymmetricAlgorithm.AesCbcPkcs7);

            var key = provider.CreateSymmetricKey(keyMaterial);

            byte[] IV = new byte[IVSize];
            Array.Copy(cipherText, IV, IV.Length);

            byte[] cipher = new byte[cipherText.Length - IVSize];
            Array.Copy(cipherText, IVSize, cipher, 0, cipher.Length);

            return WinRTCrypto.CryptographicEngine.Decrypt(key, cipher, IV);
        }

        public static byte[] GetHash(byte[] data, byte[] salt)
        {
            byte[] saltedData = new byte[data.Length + salt.Length];
            Array.Copy(salt, saltedData, salt.Length); // First we will add the salt in the begining of the saltedData
            Array.Copy(data, 0, saltedData, salt.Length, data.Length); // Appending the Data after the Salt into SaltedData

            var sha = WinRTCrypto.HashAlgorithmProvider.OpenAlgorithm(HashAlgorithm.Sha256);
            return sha.HashData(saltedData);
        }

        public static byte[] GetKeyDerivation(byte[] data, byte[] salt)
        {
            return NetFxCrypto.DeriveBytes.GetBytes(data, salt, 10000, 32);
        }

        public static string ByteArrayToString(byte[] data)
        {
            return Encoding.UTF8.GetString(data, 0, data.Length);
        }

        public static byte[] StringToByteArray(string text)
        {
            return Encoding.UTF8.GetBytes(text);
        }
    }

需要建议。。。