WebpageTest on safari shows blank page

I am using safari-5.1.7 in windows 2008r2 server. While running the tests, safari open blank page instead of redirecting to the url

I have tried installing the extension that comes with the agent, still facing the problem. What could be the issue?

When you open safari manually, does it try to load… something like 10 seconds after starting up? If not, then the extension isn’t installed or working correctly.