The whole scenario means that if value of EAX is anything less than or grater than one, the program will be a trial version & will not accept any invalid serial key. Which is the ' register failed' condition. Navigating a bit above will get a simple logic which calls a specific function, & then the function returns a result which is compared to EAX Now, once you have reached the intended memory address, you can navigate a bit up to see the ' register successful' string. & in Text string window, right click -> paste the 'Registration code is error' string ( which pops when you input wrong serial) After you find it, double click it & navigate to the memory address.

Now, to being with, fire up OllyDBG & load the A-one Video to Audio convertor EXE file in it.ĬPU window -> Search for -> All Referenced Text Strings Now as you can see, its a trial version & once you try to register it, it gives an error, & we need to find ways against it. A-one Video to Audio convertor (Download from )ĭownload & install A-one Video to Audio convertor.In any case you disagree with the above statement,stop here. You can also give a read to a step by step guide to crack Winrar to have an insight into reverse engineering & decompiling, however this one is completely different & requires little to no programming & ASM knowledge.ĭisclaimer – By Reading this tutorial You agree that this tutorial is intended for educational purposes only and the author can not be held liable for any kind of damages done whatsoever to your machine, or damages caused by some other,creative application of this tutorial. Its been some time since I have written a reverse engineering tutorial, & I thought it would be good to cover one at the dead of night :) What I am going to teach you today, is a simple reverse engineering tutorial.We will be cracking A-one Video to Audio convertor today, with just simple cracking.

How to use ollydbg to crack software