Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here




All - I recently obtained some old exe files supposedly written in FORTRAN.  I'd like to see the programming code and find out what's going on with the program.  

There are parts of the programming that I understand how it does what it does and there are parts I don't understand that have more to do with interfacing with other programs.  The latter is what I'm most interested in finding out how it works.

Are you aware of any method to "unlock" the exe so that I can see the code?


Eng-Tips Forums:Real Solutions for Real Problems Really Quick.


There is no ",A" trick like in some BASICs, so far as I'm aware.

Google produces hits on "Fortran decompiler", but I'm not aware that there actually is such a thing; the hits are mostly for sites that offer decompilers for other languages, and compilers for Fortran.

I have used several disassemblers that can take apart an .exe file and generate possible source in assembler.  I say 'possible' because no single disassembler of mine has ever produced perfectly sensible source without interaction.

You could use disassemblers to disassemble Fortran programs to which you do have source, to give you a feel for what the typical generated binaries look like.  

That exercise may or may not do you any good.  Since Fortran is not real strong on I/O, there's a fair chance that the code you're interested in was generated in some language other than Fortran, and put in the .exe by a linker.


Mike Halloran
Pembroke Pines, FL, USA


A .exe cannot be "unlocked" in the sense that something intelligible once a password is presented.  The information in a .exe is generally atomic level instructions for either the processor directly, or for an interpreter.

In either case, unless you are intimately familiar with how Fortran instructions compile into lower level code, you're SOL.  Near as I can tell, there are no readily available Fortran decompilers on the web.


FAQ731-376: Eng-Tips.com Forum Policies
Chinese prisoner wins Nobel Peace Prize


Thanks all, I appreciate the insight on this matter.

Eng-Tips Forums:Real Solutions for Real Problems Really Quick.


It is quite interesting when you compile in one language and decompile to a different language.

On the legal side there is decompiling and reverse engineering.  Very often, when you are supplied with exes, dlls or libraries, there is a clause somewhere that says you agree not to decompile or reverse engineer the code.  I think this means I promise not to take it apart to see how it works for commercial gain but I don't know if you can do it just to satisfy your own curiosity even if you are not going to use it commercially.

Also, if the company that supplied the code has gone bust and nobody has taken over, the promise is to a company that no longer exists.  Not sure about copyright law - does anyone hold the copyright?  If nobody holds it, can you still be done for breach of copyright?

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login


Low-Volume Rapid Injection Molding With 3D Printed Molds
Learn methods and guidelines for using stereolithography (SLA) 3D printed molds in the injection molding process to lower costs and lead time. Discover how this hybrid manufacturing process enables on-demand mold fabrication to quickly produce small batches of thermoplastic parts. Download Now
Design for Additive Manufacturing (DfAM)
Examine how the principles of DfAM upend many of the long-standing rules around manufacturability - allowing engineers and designers to place a part’s function at the center of their design considerations. Download Now
Taking Control of Engineering Documents
This ebook covers tips for creating and managing workflows, security best practices and protection of intellectual property, Cloud vs. on-premise software solutions, CAD file management, compliance, and more. Download Now

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close