Loupe tool problem

The problem that I am experiencing is in regards to the loupe tool zoom function not working. When attempting to show a group of students how to use the various zoom tools of Adobe Reader 9 the loupe tool would display its blue box, but would have no corresponding magnification window. This problem only showed up on a few of the machines and rebooting did solve the issue. I have gone from computer to computer in other classrooms and this problem only happens on some of them, I tried a fresh install of Adobe Reader 9 and I experienced the same problem until I closed AR9 and opened it again. I have tried researching this problem however I cannot seem to find any information on it.

I'm wondering if there are any other people who have experienced this problem and who could possibly know how to fix it.

Thank you for your time.

-Emric Phibes