Sigma OS

Sigma OS
	Crusty Windows bootleg
	The desktop of a fresh install of Sigma OS
Original OS	Windows Longhorn 4074
Release date	March 8, 2013
Author	techvortal
Country	Poland
Language(s)	English
Architecture(s)	x86 (32-bit)
File size	1.1 GB
Download link	Sigma OS 3.0 M6.iso
Date added	December 2021; Pre-Crusty Windows: October 24th, 2020

Sigma OS is a series of mods based on Windows Longhorn designed to make it more stable and "usable". It was created by techvortal and the latest version M6 was released on March 8, 2013.

Description

The OS itself is based on Longhorn build 4074, which was a Milestone 7 build of Windows Vista released in April 2004, before the development reset. The OS is mostly stock except for some integrations, icon replacements, and themes, and certain programs are taken from other Longhorn builds to make it more "stable".

Changes from Longhorn 4074

The default theme has been replaced with a theme called "Aero mod" by urban92.
Some Longhorn updates have been added.
Some icons have been replaced with ones from Windows Vista.
The cursor has been replaced with the one from Windows Vista build 5384.4.
The sounds have similarly been replaced with the ones from Windows Vista build 5384.4.
The 180 day timebomb from the original build has been removed.
Windows Update is not present.

Software

7-Zip 9.20
Paint.NET v3.36
Opera 12.14

Gallery

Setup
Installation
First boot
Empty desktop
Empty desktop (with Aero)