>> Again, none of this will prevent a determined cracker, or even a half-good one. Agreed, but what you suggest is cracked in 10 minutes, using RegSnap, RegMon and Regedit. (We use a third party copy protection scheme, which I eh... tested). It uses encrypted keys which also contain some of the information about the type of the license (time/user limited - trial or full version, etc...). Althoug I did not remove the key's encryption protection, I was always able to fool the program in extending (renewing) the evaluation time/license. I do not have an adequate answer to this problem, but maybe it is still worthwile to invest in a good third party protection program (And try to break the security yourself when you are evaluating the product so you have an idea how difficult it is for a thief to rob you from your bread and butter)