|You are pretty trusting. You may be forced into buying the software in order to unlock. I would never have used something like that.|
If you have information you don't want to share then don't place it on a hard drive. Use removable drives and lock them up or use flash drives or CDR/DVDR and lock them up. CDR/DVDR can be duplicated cheaply and easily. That would be my preference.
As stated SIW may provide a solution. Get SIW at the link below.