Hijacked Javascript Window

I generate small popup windows with javascript. I was informed by a user that the window contents were replaced with a bogus and offensive URL. How can I protect my legitimate windows.

sounds to me like either you have a program on your server causing this, or if it's only happened to that one user that they have some sort of adware/spyware that is doing this to their pages.

have you directed your user to another site with known "okay'd popups" so you cna test if it's a problem with their computer?

Problem is definitely on his computer and some sort of adware - no one else has had the "experience" on the site in question. I'm trying to find a way to combat - on my end - the hijacking of my windows since I don't know what or what isn't on someone's computer.

i really don't think there's anything you can do...you send out the javascript to the user and it runs on their machine so their machine can pretty much do whatever it wants...and it's not like you are going to be able to check anything on their computer with just javascript...i would just tell your user to download ad-aware or another program like it and maybe keep a message somewhere on your site about it...but you are hardly responsible for your users carelessness in letting spyware/adware get on their computer.