adobe product activation problem

Does anyone have problem with adobe products activation?
I have Adobe 7.0 and Photoshop CS2. After I've activated, reboot the computer, start the application, using it for like about 5 minutes, it ask me for activation code again saying because it detected hardware changed. This keep happening when I have FISR installed. I boot the clean snapshot and reinstall the adobe products, still same problem. I have to reformat the HDD, did a clean install without FISR, adobe activation problem is gone. I'm wondering if this is a known issue.