Inno Setup is a free installer for Windows programs. First introduced in 1997, Inno Setup today rivals and even surpasses many commercial installers in feature set and stability.
Key features:
* Support for all versions of Windows in use today: 7, 2008 R2, Vista, XP, 2008, 2003, 2000, Me, 98, 95, and NT 4.0. (No service packs are required.)
* Extensive support for installation of 64-bit applications on the 64-bit editions of Windows. Both the x64 and Itanium architectures are supported. (On the Itanium architecture, Service Pack 1 or later is required on Windows Server 2003 to install in 64-bit mode.)
* Supports creation of a single EXE to install your program for easy online distribution. Disk spanning is also supported.
* Standard Windows 2000/XP-style wizard interface.
* Customizable setup types, e.g. Full, Minimal, Custom.
* Complete uninstall capabilities.
* Installation of files:
Includes integrated support for "deflate", bzip2, and 7-Zip LZMA/LZMA2 file compression. The installer has the ability to compare file version info, replace in-use files, use shared file counting, register DLL/OCX's and type libraries, and install fonts.
* Creation of shortcuts anywhere, including in the Start Menu and on the desktop.
* Creation of registry and .INI entries.
* Running other programs before, during or after install.
* Support for multilingual installs, including right-to-left language support.
* Support for passworded and encrypted installs.
* Support for digitally signed installs and uninstalls.
* Silent install and uninstall.
* Unicode installs. (Windows 2000/XP or later)
* Integrated Pascal scripting engine option for advanced run-time install and uninstall customization.
* Full source code is available (Borland Delphi 2.0-5.0 and 2009).

Home Page - http://www.jrsoftware.org/isinfo.php