Is there a way to generate different contents in a zip file based on a password?

Question

For example, I email a zip file to three friends. I give one password to two friends but a different one to my third friend to unlock different files than my other two friends.

It can be done by developing a program, but I'm not looking to make it an .exe. Can anyone think of any way to do this if not with a .zip?

Answer 1

Yes, this can be done without developing a program:

• Create a passworded ZIP of the first file.
• Open the resulting .zip with WinRAR.
• Add files to archive, choose the second file and set a different password (on Advanced tab).

All friends will be able to see the file list, but they will only be able to view/extract the file of which they have the password.

Answer 2

Maybe my idea isn't exactly what you are looking for, but what you could do is create an encrypted volume (~file) with TrueCrypt in which you create a hidden volume .

That way you can send one file to all three friends and based on the passwords you give them, they'll see different contents. TrueCrypt will however not compress the files, only encrypt them.