We recently upgraded all clients in our domain to IE7. Since then, users cannot view YouTube properly. Firefox works, but I don't want users using Firefox; one more application that I don't need to continuously monitor security updates with.
 
Viewing YouTube the first time works fine, but as soon as you visit another link, it looks all sorts of crazy, almost like plain text and everything is aligned on the right. It also shows the infamous message: "Hello, you either have JavaScript turned off or an old version of Adobe's Flash Player." Flash Player is up to date and JavaScript is enabled. I've uninstalled and reinstalled Flash, but to no avail. I've tried all the suggestions that I've found, but it won't work. Clearing the temporary internet files work, but only once and then you'll have to clear the cache for everytime you want to view a YouTube video.
 
If a machine is outside of our domain, YouTube operates normally. I've looked through settings and can't find a resolution. This isn't a huge deal, but it's annoying the hell out of me, and users are starting to complain more and more to me about it, which just plain aggrevates me; when they're happy, I'm happy.
 
Any help would be greatly appreciated.