XAMPP 2.5!! I don't see any version of XAMPP 2.5, latest is 1.8.1. I haven't used it though.
The solution you applied will work with XAMPP 1.7.7 because in this version of xampp there is some openssl version problem.
You must TRY mohammaed moreb's solution and yeah don't forget to set environment variable.
Good Luck