The message of confirmation to write on the drive hard when we are on a CD

hello!

I have installed PortableFirefox on a CD. On this CD, I have put too a web site.
My aim is that I can launch the main page of my web site with PortableFirefox. I have no problem for make this. But as it's a CD, I can't write on this last and at the launch of PortableFirefox, I have a message which ask me to accept that the program writes on my hard drive.

how make for take no notice this option and write on the hard drive be automatic? (without message of confirmation)

Sorry for my bad english, i'm french!
Thank you
Aud-