Repetitive Error when testing site

Hello,

This might sound like a silly question but I keep on getting this error.

The testing completed but failed.
Failed to configure IPFW/dummynet. Is it installed?
Waterfall Screen Shot Video
First View: Test Data Missing
Repeat View: Test Error: Skipped repeat view, first view failed: Failed to configure IPFW/dummynet. Is it installed?

Before testing was always fine, without modification on the server / site it no longer functions.

Does anyone know why it is so?

Do you have a link to a test result? That is a configuration problem on the test machine so I’ll need to track down which one.

Thank you very much for your response.

Just saw that it works again. When performing a test to give you a link, it showed results.

Earlier it gave this result http://www.webpagetest.org/result/140817_XH_H21/

I am facing the same issue and inspite of being getting this installed on 32 bit, it is creating issue. i have WINDOWS 2008 Server (on VM) and 32 bit.

I’m was getting this a lot yesterday and is continuing today. Here’s a link to a test:
http://www.webpagetest.org/result/150630_G8_N3K/