Sagepay form submit parameters in PHP - php

Question

How many parameters I need to pass the in form ULR ,It can interact with sagepay payment gateway. Following parameters are I have passed in the form url but I ma getting the following error:
Error:
Error number:
5068
Error message:
The encryption method is not supported by this protocol version.
I am unable to connect the sagepay server payment.I am completly new about the configuration of sagepay payment.
Some one can please tell me how many parameter I need to pass and What are they are?
How to encrypt the values and then pass the values?
Code:
<form name='sagepay' action='{$pm_sagepay_url}' method='post' onsubmit='this.submit.disabled=true;return true;'>
<input type='hidden' name='VPSProtocol' value='3.00'>
<input type='hidden' name='TxType' value= 'PAYMENT'>
<input type='hidden' name='Vendor' value= 'protxross'>
<input type='hidden' name='Crypt' value= 'TPjs72eMz5qBnaTa'>
<input type='hidden' name='cmd' value='_xclick'>
<input type='hidden' name='business' value='{$this->pm_sagepay_business}'>
<input type='hidden' name='item_name' value='".$order->order_description()."'>
<input type='hidden' name='amount' value='".sprintf("%01.2F", ($order->order_total_price-$order->order_fee))."'>
<input type='hidden' name='handling' value='".($order->order_fee)."'>
<input type='hidden' name='return' value='".$_SHOP->root_secured. 'checkout_accept.php?'.$order->EncodeSecureCode()."'>
<input type='hidden' name='notify_url' value='".$_SHOP->root_secured. 'checkout_notify.php?'.$order->EncodeSecureCode()."&setlang={$_SHOP->lang}'>
<input type='hidden' name='cancel_return' value='".$_SHOP->root_secured. 'checkout_cancel.php?'.$order->EncodeSecureCode()."'>
<input type='hidden' name='currency_code' value='{$_SHOP->organizer_currency}'>
<input type='hidden' name='undefined_quantity' value='0'>
<input type='hidden' name='no_shipping' value='1'>
<input type='hidden' name='no_note' value='1'>
<input type='hidden' name='rm' value='2'>
<input type='hidden' name='invoice' value='{$order->order_id}'>
<div align='right'>
<input type='submit' value='{!pay!}' name='submit2' alt='{!sagepay_pay!}' >
</div>
</form>";

Answer 1

The info added to the form needs to be encrypted you be better off using the guide found here:
http://www.sagepay.co.uk/file/12241/download-document/FORM_Integration_and_Protocol_Guidelines_010814.pdf?token=gMABp5MzTV1BevfFpoTFkrofFWwHXySRM5tzGIdKj3Q
Also this guy has made a basic script for the form i got the main form to send it was the success page i could not get to work but i have now so if you get stuck give me a shout..
https://github.com/tolzhabayev/sagepayForm-php