i am trying to do integrate ccavenue payment gateway , where i am getting error as -encrypted request Invalid

Question

I am using Php version 7 with xampp v.3.2.2, where i am trying to run ccavenue html page and getting error saying encrypted request Invalid. In php.ini I have something like(;mcrypt.algorithms_dir=) and (;mcrypt.modes_dir=) whether i have to mention something there to run ccavenue handler pages.

I included extension =mcrypt.dll