I found this small utility to deactivate DeepFreeze. It run from PE, in fact if you download from the author's site, you download the whole LiveCD. The software itself is so tiny, about 17kb, so I upload it here in case someone need it.
I tried it with DeepFreeze 6.2 and it works.
Then I tried with DeepFreeze 6.5. It works , but not perfectly. When I reboot, deepfreeze.exe ( or deepfrz.exe ?) still running. I kill it through TaskManager and delete the installation folder. However the deepfreeze itself has deactivate. I read somewhere that the exe in the instalation folder, deepfreeze.exe, is merely a decoy. The real program itself run in kernel level and has nothing to do with the exe in instalation folder.
The utility itself is in Spanish (?) language, the only thing you need to do is tell it where Windows directory and operating system is, klik "Eliminar Por Completo DeepFreeze" button. Put file eliminar_deepfreeze.reg in the same folder with the utility.
I don't know if this utility breaking this forum rule or not. I'm sure it's not warez and the author give it freely. But its kind of hacking tool right? If I break the rule, please let me know and I'll delete this post.