Adobe Flash Player

I'm running Windows XP with all the updates and service packs. My browser is I.E. 7 with all the updates and service packs. I've downloaded and installed Adobe Flash Player at least 10 times. This works temporarily, but whenever I do either a hard or soft boot, I lose the Adobe Flash Playe as an add-on for Internet Explorer 7.0. Does anyone have any ideas/suggestions as to why this is occurring and how to fix this problem?

Thanks for any help.