I lost the source code from one project I did on the company I&#39;m working for and haven&#39;t been able to find a Visual Basic 6 decompiler; does that even exists?

I only have the EXE that I&#39;ve rescued from a user&#39;s machine.

Is there a Visual Basic 6 decompiler?

A friend of mine downloaded some malware from Facebook, and I&#39;m curious to see what it does without infecting myself. I know that you can&#39;t really decompile an .exe, but can I at least view it in Assembly or attach a debugger? 

Edit to say it is not a .NET executable, no CLI header.

Is it possible to &quot;decompile&quot; a Windows .exe? Or at least view the Assembly?

So I&#39;ve just realized how easy it is to decompile my Java code. I&#39;ve been searching around the net and I can&#39;t seem to figure out *WHY* its so easy. Every time I google something like &quot;Why can I decomilple `.class` files?&quot; or &quot;Why does Java decompile so easily&quot;, all I get is links to software that can easily deompile my code. So I turn to you StackOverflow: why is it that Java can be converted back to easlily readable source code while C++ and other languages aren&#39;t very friendly to decompiling?

Thanks

Why is it so easy to decompile Java Code?

I accidently erased my project from [Eclipse][1], and all I have left is the [APK][2] file which I transferred to my phone. Is there a way to reverse the process of exporting an application to the .apk file, so I can get my project back?

  [1]: http://en.wikipedia.org/wiki/Eclipse_%28software%29
  [2]: http://en.wikipedia.org/wiki/APK_%28file_format%29


Reverse engineering from an APK file to a project

I wrote a C# application for a client a couple of years ago, but I no longer have the source code.  All I have is the EXE that I deployed on the client&#39;s PC.  Is there a way I can generate C# source code from the EXE?

How do I decompile a .NET EXE into readable C# source code?

Is it possible to get some information out of the .pyc file that is generated from a .py file?

Is it possible to decompile a compiled .pyc file into a .py file?

Is there a way to extract the source code from an executable .jar file (Java ME)? 

Extract source code from .jar file

Is it possible to decompile an APK package or DEX file on Android platform?
Are there any tools that can decompile an APK file?


How to decompile an APK or DEX file on Android platform?

I have a program in which I&#39;ve lost the C++ source code.  Are there any good C++ decompilers out there?

I&#39;ve already ran across [Boomerang][1].


  [1]: http://boomerang.sourceforge.net/

Is there a C++ decompiler?

This question has been [asked][1] [before][2], but each time the accepted answer is simply a resignation to provide function descriptions using `Application.MacroOptions` ([VBA6][3]) ([VBA7][4]), but this information does not actually appear as a tooltip, so it does not solve my problem.

**The Goal**

What we all desire is to be able to define custom functions by any means (VBA, VSTO, or COM add-in) and give the user the benefit of a pop-up/tool-tip description of the function and its parameters, as appears for every built-in Excel function, either inline or in the formula bar: 

![enter image description here][5]

![enter image description here][6]

The widely accepted answer to this need is that it is not possible for custom functions, but I wish to challenge that belief.

**The Problem**

Currently, the best I&#39;ve seen anyone do is to define functions (often using the above MacroOptions call) so that when bringing up the function dialog (the fx button in the formula bar) their function and parameter descriptions appear as below:

![enter image description here][7]

As you can see, this is a complicated function with many parameters. If the user is not aware of this &quot;function arguments&quot; dialogue and how to bring it up, and are instead familiar only with Excel&#39;s standard tooltip, they will only see the formula name and no additional help:

![enter image description here][8]

With which they have no chance of correctly providing the required parameters. (Without reading the documentation, which of course, no user ever does.)

Now, a power user might know that by typing &lt;kbd&gt;Ctrl&lt;/kbd&gt;+&lt;kbd&gt;Shift&lt;/kbd&gt;+&lt;kbd&gt;A&lt;/kbd&gt;, they will be granted a auto-completed list of function parameters like so:

![enter image description here][9]

But of course, we have the same problem as above which is that standard excel users will only be used to the default behavior from the first image and will probably never have learned that feature.

It should be clear by this point why this isn&#39;t enough and we want what every built in function has - the in-line tool-tip that tells the user how to use the function.

**The Tease**

At first, I might have been convinced that this simply isn&#39;t possible except with the native Excel application functions. Add-ins and VBA are extensibility features, and this tool-tip may simply not be extensible. But that theory is challenged by the existence of the Analysis Toolpak add-in. Sure, it&#39;s built in Microsoft, but ANALYS32.xll is a standalone XLL add-in just like those that can be produced in VB, C, C++, and C#. Sure enough, when this XLL is loaded into the application the [functions][10] that it makes available have the same tool-tips of native excel functions:

![enter image description here][11]

Surely if this information is somehow encoded in this XLL file and passed on to Excel, there is a way to replicate it with our own Add-ins? I&#39;m at the point now where I&#39;m going to start teaching myself a little about decompiling and seeing if I can reverse-engineer whatever is going on in the analysis toolpak.

**How You Can Help**

I&#39;m almost certain that I&#39;ve researched all the publicly available information there is about this problem. If someone knows something I don&#39;t know that might help with this though, feel free to chime in. I am very unfamiliar with reverse-engineering compiled dlls / xlls, so if someone feels like popping open their local copy of Analysis32.xll and figuring out what&#39;s going on with it&#39;s custom function definitions, I would be much obliged. Otherwise, I&#39;ll just keep digging into this myself until I&#39;ve hit all the dead ends and report back what I find.


  [1]: https://stackoverflow.com/questions/4262421/how-to-put-a-tooltip-on-a-user-defined-function
  [2]: https://stackoverflow.com/questions/5282128/documenting-vba-code-for-excel-auto-complete
  [3]: http://msdn.microsoft.com/en-us/library/aa195786.aspx
  [4]: http://msdn.microsoft.com/en-us/library/office/ff838997.aspx
  [5]: http://i.stack.imgur.com/Jj8bS.png
  [6]: http://i.stack.imgur.com/804qz.png
  [7]: http://i.stack.imgur.com/8Osto.png
  [8]: http://i.stack.imgur.com/3haBg.png
  [9]: http://i.stack.imgur.com/cY7j3.png
  [10]: http://support.microsoft.com/kb/291058#MORE%20INFORMATION
  [11]: http://i.stack.imgur.com/Szn0q.png

The quest for the Excel custom function tooltip

How do I lock compiled Java classes to prevent decompilation?

I know this must be very well discussed topic on the Internet, but I could not come to any conclusion after referring them.

Many people do suggest obfuscator, but they just do renaming of classes, methods, and fields with tough-to-remember character sequences but what about sensitive constant values?

For example, you have developed the encryption and decryption component based on a password based encryption technique. Now in this case, any average Java person can use [JAD][1] to decompile the class file and easily retrieve the password value (defined as constant) as well as [salt][2] and in turn can decrypt the data by writing small independent program!

Or should such sensitive components be built in native code (for example, VC++) and call them via [JNI][3]?

  [1]: http://www.kpdus.com/jad.html
  [2]: http://en.wikipedia.org/wiki/Salt_%28cryptography%29
  [3]: http://en.wikipedia.org/wiki/Java_Native_Interface


How to lock compiled Java classes to prevent decompilation?

IDEA has a great built-in feature - decompiler. It works great.I can copy source code, but I cannot find option to extract all decompiled java classes to java files.   
This project has a lot of java classes and packages, so I will be to long to copy this manually.  
Does anyone know how to extract to java source files.
  Thx

How to decompile to java files intellij idea

I am the maintainer of a site that has allegedly &#39;lost&#39; the source code to a flash swf file.  How do I decompile this source?

Are there any programs online or offline that I could use?

How do you decompile a swf file

Are the users able to convert the apk file of my application back to the actual code?
If they do - is there any way to prevent this?

Is it possible to decompile an Android .apk file?

Java `.class` files can be decompiled fairly easily. How can I protect my database if I have to use the login data in the code?

How can I protect MySQL username and password from decompiling?

I need to modify an existing APK, modify the sources and then recompile it.

 - I can decompile it using dex2jar or apktool, it&#39;s working great 
 - From the jar file I can obtain the java sources (using jd-gui)
 - Then I can modify the java files

But now I would like to know how to recompile the java files and put them back into a jar file! (the jar part should be easy, the main problem seems to be how to recompile the java files for android)

I know that an other solution is to use apktool and then modify the smali files, but it seems to be really complicated when we want to add a lot of code!

My application is a basic a HelloWorld whitout obfuscation.

Decompile an APK, modify it and then recompile it

One if the first things I learned when I started with C# was the most important one. You can decompile any .NET assembly with Reflector or other tools. Many developers are not aware of this fact and most of them are shocked when I show them their source code.

Protection against decompilation is still a difficult task. I am still looking for a fast, easy and secure way to do it. I don&#39;t want to obfuscate my code so my method names will be a,b,c or so. Reflector or other tools should be unable to recognize my application as .NET assembly at all. I know about some tools already but they are very expensive. Is there any other way to protect my applications?

EDIT:

The reason for my question is not to prevent piracy. I only want to stop competitors from reading my code. I know they will and they already did. They even told me so.
Maybe I am a bit paranoid but business rivals reading my code doesn&#39;t make me feel good. 




How can I protect my .NET assemblies from decompilation?

As we know, Android apps are written in Java. In Java, no matter [what you do][1], it is impossible to protect compiled code from decompilation or reverse-engineering, as the Stack Overflow question *[How to lock compiled Java classes to prevent decompilation?][2]* suggests.

How would one go about protecting an app that contains algorithmic trade secrets from reverse-engineering?

By &quot;how&quot; I mean not only software techniques, but also other **creative** approaches.

  [1]: http://www.galkonline.com/2010/09/15/how-to-prevent-java-from-being-decompiled/
  [2]: https://stackoverflow.com/questions/49379/how-to-lock-compiled-java-classes-to-prevent-decompilation


Is it really impossible to protect Android apps from reverse engineering?

The hard drive on my laptop just crashed and I lost all the source code for an app that I have been working on for the past two months.
All I have is the APK file that is stored in my email from when I sent it to a friend. 

Is there any way to extract my source code from this APK file?

All Decompiling Solutions on Gang of Coders

Total of 19 Decompiling Solutions