If you forget your password for compressed archive (rar, 7z, zip), RarCrack is the solution. RarCrack uses a brute-force algorithm to find correct password. You can specify which characters will be used in password generations.
Preparing your system for installation
Install the following package
[email protected]:~$ aptitude install libxml2-dev build-essential
Download the latest version of rarcrack from here
[email protected]:~$ wgethttp://sourceforge.net/projects/rarcrack/files/rarcrack-0.2/%5BUnnamed%20release%5D/rarcrack-0.2.tar.bz2/download
rarcrack your_encrypted_archive.ext [–threads thread_num] [–type rar|zip|7z]
Example with a rar-file, 7z-file, and zip-file