Problems with different players and my website

Hey Guys,
I just got done with the “beta” of one of my websites that has a navigation header made in Flash CS4. The thing works flawlessly on my own machines, however, if I try to view it on my friends computers it does not work. The flash gets stuck in an infinite animation loop (even though everything has stop actions where needed). I believe this is because he has an older version of flash player installed… so my question is. How do I make it to where users with older players will see what they should?

Thank you!