I'm using PayPal sandbox for the payment gateway, this is first time I'm trying to inbuild payment gateway to my site.
I simply used the form tag as follows
<form target="paypal" method="post" action="http://www.sandbox.paypal.com/cgi-bin/webscr">
With other details, I tried both http and https here, but it is sending me to a page where it ask me to login to PayPal with following message:
Please login to use the PayPal Sandbox features.
I don't have an idea what to do now. Am I doing something wrong in code? Please direct me what exactly the procedure to inbuild PayPal service to site.