I am looking at a program called chat watch. Looks like Blowfish protection.

I decieded to do it the easy way and went looking for a patch.
Current version is 2.5.2

Best I can find is 2.5.1

Since the patcher is using a generic patcher "File created by ScAEvoLa's PatchEngine" Then I though well why not find out how 2.5.1 was patched and do the same.

So reverse engineering the Patcher i.e. Something Different.

What happens when you have generated the patch and can't find the same software again. Your stuck if you can't reverse the patcher.

Anyone interested search for chat watcher to find the right patcher.

I wish people would list how they attacked a certain product so that other people can understand the method rather than a generic patch

You may get lucky by taking the patcher apart.

But all it is likely to tell you is that bytes at particular offsets where nopped.

If you strike really lucky the patcher will check the bytes before patching them, from that you may be able to assertain what instructions where patched.

However in reality that is likely to be less than useless as it is probably a jnz xxxx and theres many occurences of those in every app.

The only thing I can sensably suggest is to look for an site with the older version still available for download, then work from there.

Kilby...

Kilby is right. Most patch engines simply create a CRC of the file and if it matches, they blatantly write over the old code with the patched code. This gives you nothing.

So what you need to do is fine version 2.5.1 on the 'net, download it, and then copy the exe somewhere before patching it, and afterwards find the differences using something like FC. One done, find the equivalent locations in the new file.

Or have the fun reversing and patching it yourself?

Well that was no fun Found and registered it within a few secs... Didn't even need to patch it.

@Iwarez

Not everything has to do with cracking but understanding.

I bypassed the protection in little time but the main aim I did it was to wonder if it was possible to work out from a previous version to do the next version.

Problem with this one is that its Visual basic 6.0. Still wish I had a decoder for CODE recovery for VB6.0. People call this a decompiler.

oh well

life goes on.

If you want somthing with the same protection over several versions I have a couple of products in the house like that.

Once I get the titles I will pass them on, meanwhile secure CRT and other vandyke products have the possibility of a generic patch if you want to try that.

Thought I like their products so much I actually buy them (now that I have a little money).

Kilby...

So the fun was to look how someone else patched it the previous time and if it was possible to recreate the patch for the new version?

Why not.

Hell I look at weird shit but at I learnt something.

Sometimes the weirdest stuff will lead you to interesting stuff.