hi all
for a longer time know I´m trying to find a serial for File-Ex 2.12d which can be downloaded at www.file-ex.com (in case you need further information).
The Problem about this program is that it´s written in visual c++ 3.0 which means 16 bit code.
As i read in a tutorial of razzia I decided to look where the serial entered is taken to by bpr on es:di. It seems that the program generates a value from the serial by shifting the bits to the left. for example 112 = one hundred and twelve.
Than it does something to this value to encrypt it and compares it to another value. There is no echo in memory to be found. I think the only way to reverse it is to reverse the value with which it is compared, but i cant seem to find the routine where its encrypted and how.
It might be that I´m mistaken so please have a look at the program or give me some hints to crack it. Any good tutorials would also be fine.

many thanks in advance

siRl

Hi,
It's a long time since I did this so this is from memory. I don't remember there being any encryption, what I think you see
happening is your 32 bit sn being converted
to two hex words, then they are simple compared with the "real" ones, check it out by just entering '1234' and see if it end up with 4d2 in one of the regs.
regards

No Name in case I'm wrong :-)

hi

many thanks for the help, because I cracked it now and I will try to keygen it.
The hint you gave me was the last bit I needed to understand the whole protection.

siRl