>Then, if serial number may be modified, is not a good idea
>to protect an application from copy using HD´s serial numbers.
>
>There is another way to protect an application from copy (in VFP 5.0)?
>
> Thank you.
Yes there are very simple and complex ways (in Turkey you have to specialize in protection). How could I mention protection on a public place :)
There are some I could mention for I don't use or doesn't matter if I do too.
-One is hardlock keys. They're easy to use and I used HASP with Fox easily.
-The other is the one I used in past. I dropped using it for it was hard to implement. You had to compile each party separately because there wasn't a way to know the values from one to other. Funny, what I did is to make physical defects on a diskette. From software I was then first finding the defective places and poking values to my program. My program in turn was seeking those points + verifying neighbours are not physically bad + checking if the defects were electronically correctable (shouldn't be). You think I'm crazy :) Well I did that years ago. The bad thing, if customer ever loses his diskette than I have to create a new one and recompile.
An easier one is to create extra, non standart sectors on diskette and write there some info. Programmatically you would set those diskette parameters and read back. Well I dropped that too because it's one of the schemas every protector thinks first :) Plus it also requires a diskette.
-A diskette drive has 12 parameters that you could alter and use some of them. But forget it now for I always found it hard to implement (maybe you would do easily - Norton was saying "as far as I remember" directly programming the NEC controller is one the thoughest to hack).
-You can write some value to registry. While registry could be read simply, I "believe" people who could find the correct key and value are rare. I think those who are capable of doing that deserve to use my app for free :)
-Another very simple yet enough for nonprofessionals is to write a dummy file (or just a few bytes) to somewhere. Even a 40Mb disk had many hideouts to write it :)
-One final note just to force your imagination : Even a table has many hideouts. Don't undertake sys(2007). In pure fox simple protections could be done. Never use timings as protection (I had my lesson before:).
BTW yet serialnumber could be changed, few notice and/or think it :)
As Peter Norton said, your imagination is the key to create a good protection.
But all in all, I never saw a protection that cannot be broken. Only you can make the life harder for hackers and they always win.
Cetin
