View Full Version : Restrict Software to work on a perticular PC

17-01-2008, 07:29 AM

I am not sure, this might not be the right forum for this question. I know there
are many scholars here who can guide me thus I thought to ask this question

Some of the software works on single PC only. If we install the operating
system again then also work on that PC only with the allocated Registration Key.

Can anybody explain the concept, mainly how it is detecting the same PC?
I guess it is detecting the motherboard. But How? What exactly it is
detecting? And How it works? I know C language. And I want to make one
simple software to test like this.

In one software I bought, it works following way.
1. Install the free version( without any registration key )

2. When we start the software, it generate one unique product code.
It is displaying that product code which ca not be modify by us. Just read only.
And with empty box for registration key.
( Guess: This might be detecting the motherboard ID and generate one
code in relation to that. Thus if we reinstall the operating system then
it again read the motherboard ID and generate the similar code. And it
might be saving this code in the registry for later use )

3. Then they ask us the product code generated for our evaluation software.
And send us one registration code which will work only for this PC.
If we reinstall the operating system and install that software again then
it will generate the same product code and work with the same registration

How can we make this?
Thanks in advance,

17-01-2008, 07:47 AM
I think if you installed it on another PC and used the same code it would work.

Most software that works on one PC only phones home to see if that number is used or not, if the host sees it is already used then it will reject it for use on another PC.

Even Windows would be able to be installed on more than one PC with the same serial, it is not until you have to update it or authenticate it that you would run into problems.

17-01-2008, 08:00 AM
There are areas on the Hard Drive that never get wiped even with a format (ask a forensic computer tech). These are protected areas and this is (maybe) where it is storing its information.

But I prefer Bantu idea.

17-01-2008, 11:40 AM
There are a number of ways you could do what you wont.

Mark the HDD. As mentioned parts of the HDD are not used in normal usage and could be used to hold a finger print.

You could also use the BIOS ACPI table to hold a finger print.

Most HDD have a unique serial number that you could use as one part of your finger print along with say the PNP BIOS table & ACPI table that will identify most of the other PC hardware.

There are many commercial products that you could use to do what you wont if you do not wont to go down the path of learning yourself.

Graham L
17-01-2008, 06:32 PM
Intel Pentium III CPU chips have a unique identification number. This was to enable reliable code protection, among other things.

I remember some large mainframe computers had their ID numbers set with wire jumpers.

Intel met enough consumer resistance to take the feature out of later CPUs.