Encoding and Decoding Password in login form in asp.net <p>I am making a Registration and a login Form with encoded password saved to database, I can encode the password using encoding.utf8.</p> <p>Problem is I register with some username and password and the data get saved to database with encoded password, but when I login with the same data it shows me this below error. </p> <p><strong>Invalid length for a Base-64 char array or string.</strong></p> <p>Can anyone give me the described solution for this. Below I am attaching my encoded and decoded methods :</p> <p><strong>Encoded :</strong></p> <pre><code> private string encryption(string clearText) { string encryptkey = "123"; byte[] clearBytes = Encoding.Unicode.GetBytes(clearText); using (Aes encrypt = Aes.Create()) { Rfc2898DeriveBytes rdb = new Rfc2898DeriveBytes(encryptkey, new byte[] { 0x49, 0x76, 0x61, 0x6e, 0x20, 0x4d, 0x65, 0x64, 0x76, 0x65, 0x64, 0x65, 0x76 }); encrypt.Key = rdb.GetBytes(32); encrypt.IV = rdb.GetBytes(16); using (MemoryStream ms = new MemoryStream()) { using (CryptoStream cst = new CryptoStream(ms, encrypt.CreateEncryptor(), CryptoStreamMode.Write)) { cst.Write(clearBytes, 0, clearBytes.Length); cst.Close(); } clearText = Convert.ToBase64String(ms.ToArray()); } } return clearText; </code></pre> <p><strong>Decoded:</strong> </p> <pre><code> private string decryp(string cipherText) { cipherText = cipherText.Replace(" ", "+"); string decryptkey = "123"; byte[] cipherBytes = Convert.FromBase64String(cipherText.Replace(" ", "+")); using (Aes encrypt = Aes.Create()) { Rfc2898DeriveBytes rdb = new Rfc2898DeriveBytes(decryptkey, new byte[] { 0x49, 0x76, 0x61, 0x6e, 0x20, 0x4d, 0x65, 0x64, 0x76, 0x65, 0x64, 0x65, 0x76 }); encrypt.Key = rdb.GetBytes(32); encrypt.IV = rdb.GetBytes(16); using (MemoryStream ms = new MemoryStream()) { using (CryptoStream cst = new CryptoStream(ms, encrypt.CreateDecryptor(), CryptoStreamMode.Write)) { cst.Write(cipherBytes, 0, cipherBytes.Length); cst.Close(); } cipherText = Encoding.Unicode.GetString(ms.ToArray()); } } return cipherText; </code></pre> <p>Any help would be appreciated ! </p>