Decryption of string in C#

//This class is for decrypt the encrypted value
//call this method with two parameters text and key "01AB=$6Q"

class DecryptClass
{

public static string Decrypt(string text, string key)
{

byte[] encodedkey;
byte[] iv = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };
byte[] bytes;

encodedkey = Encoding.UTF8.GetBytes(key);
DESCryptoServiceProvider csp = new DESCryptoServiceProvider();

bytes = Convert.FromBase64String(text);

MemoryStream ms = new MemoryStream();

try
{
CryptoStream cs = new CryptoStream(ms, csp.CreateDecryptor(encodedkey, iv),CryptoStreamMode.Write);
cs.Write(bytes, 0, bytes.Length);
cs.FlushFinalBlock();
}
catch (Exception ex)
{
Logger.LogInfo(ex);
}

return Encoding.UTF8.GetString(ms.ToArray());

}

}