Please ask questions ONLY in this topic.

[OnlyHuman]

Yeah, you'll most likely get zapped with a spoiler for that. You might want to save yourself some trouble and remove the bulk of it yourself. Another thing, it's possible to complete this challenge using only programs or scripts that you develop yourself. No need to download anything. If you're completely stuck, there is a thread in the Crypto section of this site, that details the algorithm like no other source available.

[dark_fighter]

that was fun!!! actualy the encryption can be break quite easy... the only "hard" part of this mission is the paperwork that you have to do after you understand the encryption algorithm...
and here is my hint to save some time (hope it's not a spoiler, if it is, please remove it):

when you understand the algorithm search for an ASCII table and look close!!!

[n00bday]

All right. This one's got me feeling like a super-idiot. What I know so far: the letters are blocks of three, e.g.: .xxx.xxx.xxx = letter. I know (from reading this forum) that the three numbers are related a certain way. What I want to know is -how- did you figure that out? I've tried lots of things. I've tried inputting the same letter with the same password, but it doesn't yield the same results. I've tried doing words like "seen", "been", etc. with the same password and still no luck finding similar instances.

I understand frequency-analysis (as you could probably tell by my example words), but this just goes right over my head. I -know- the solution to the numbers because it's in the forum, but I would like to -understand- how in the Hell you came to that solution as a logical conclusion. It's far beyond me. Thanks.

[DRobberts]

I've just decrypted this message within an hour, without any help (almost the first time for hard Realistic missions). So I guess I can explain the method to manage the mission.

I advise you to try with very very simple examples to well understand the encryption mechanism. "been" and "seen" are simple but not enought, trying with one letter for the message and one letter for the key must be a good start. And you should change only 1 parameter at a time in order to see how it weights on the result. Then you should analyse the resultS of your tests and try to find a faillure in the mechanism, something caracteristic of what you have encryted (both the key and the message)...
Think about it, this first step is not very difficult but you have to try basic examples untill you well understand how the encription mechanism works.

[kureta]

I have been a member here for some time but I have never posted on the forums. And I have been away for quite a while. Now the forum system has changed and I cannot send PMs. I have solved this one but I can't send it.

-- Mon Mar 21, 2011 3:04 am --

I guess I have to make some forum posts to activate PMs...

[Phantom Wolf]

I have been a member here for some time but I have never posted on the forums. And I have been away for quite a while. Now the forum system has changed and I cannot send PMs. I have solved this one but I can't send it.

-- Mon Mar 21, 2011 3:04 am --

I guess I have to make some forum posts to activate PMs...

You're supposed to use the "HTS Messages center", not the forum's PM system

[trandoanhung1991]

This one is really simple.

What you need to do is to understand how XECryption works. It's like this:
[Do some stuff] -- Goatboy

Now, to break this encryption is really easy. There are no repeating patterns, BUT there is a huge flaw. (hint: most common character).

Good luck.

[fashizzlepop]

Thanks for the useless post and unappreciated spoilers. Now, please go edit that.

[mkylman]

This was really fun! I wrote a C++ program to decrypt it...took me two hours to figure it out >.<

[fashizzlepop]

Go, You! ^