Decrypt given data previously encoded with rc2-64 cipher algo. RC2 with a 64-bit key size, offering a stronger encryption than RC2-40 but still weaker than modern algorithms. RC2-64 was an intermediate option for providing stronger encryption in environments where RC2-128 was not an option. RC2-64 is still weak and considered insecure for most modern applications due to its vulnerability to modern attacks. Our decryption process assumes the IV string is prepended in the encoded string during the encryption process. You can not decrypt and get the correct results if the IV or passphrase mismatch occurs between encryption and decryption process.