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 every Windows release since 2000, including: Windows 8, Windows Server 2012, Windows 7, Windows Server 2008 R2, Windows Vista, Windows Server 2008, Windows XP, Windows Server 2003, and Windows 2000. (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.
Integrated preprocessor option for advanced compile-time customization.
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).

5.5.4 (2013-10-13)

Added the Windows 8.1 "compatibility" section to the various manifest resources used by Inno Setup. This enables any check for the operating system version to get the real version number (6.3) instead of getting the same version number as it did in Windows 8 (6.2).
Compiler IDE: Added new option: Show line numbers in gutter (default: off).
Pascal Scripting changes:
Added new event function CurInstallProgressChanged, which you can use to monitor progress while Setup is extracting files, creating shortcuts, creating INI entries, and creating registry entries. See the help file and the CodeExample1.iss example script for more information. Contributed by TLama via GitHub.
WizardForm.BeveledLabel visibility is now automatically handled even if its caption was set from

.
Unicode

based on RemObjects Pascal Script Git commit 538905910852bcbeef646f26592a973d15d3d5ec.
Minor tweaks.

Home:

http://www.jrsoftware.org

Download:

http://www.jrsoftware.org/isdl.php