Windows XP with IE 8 LMS reporting issue

I am working on a Captivate 6 project (Captivate 6 installed on OS - Windows 7).

In my project i have a button which reports a score to LMS which is working fine as required when tested on Moodle with Window 7 OS and IE 8, but score does not pass when i test the same version with Windows XP and IE 8 on moodle.
can anyone please help me solve this problem.

thanks in advance.