reactOS logo png transparentA brand new version of the open source Windows clone ReactOS is available to download.

The latest effort to result from the switch to a faster release cadence, ReactOS 0.4.9 comes packing a stack of smaller changes than previous versions, with focus firmly on improving the overall system stability, usability, and UI consistency.

We’ll take a closer look at the key improvements and features of ReactOS 0.4.9 in a second.

First, a quick recap of what this free Windows alternative is all about.

What is ReactOS?

reactos 0.4.9 screenshot

The first thing it’s important to note is that ReactOS is not based on Linux.

It is an alternative operating system designed from the ground up to behave, work and look like classic Windows.

It uses a custom NT-like “kernel”, ships with a WIN32 subsystem, and features Windows driver compatibility.

Useful applications and tools come installed default, and the RAPPS package manager (similar to Synaptic on Linux) makes installing new apps, modules and tools easier and safer than on a real Windows OS.

With Microsoft unlikely to make Windows open source it is left to ReactOS to imagine the “what ifs?”

Despite being around for almost as long as the Spice Girls ReactOS is not trying to replace Linux as world’s third favourite OS.

As the project wiki page explains, ReactOS is an open source “replacement for Windows users who want a Windows replacement that behaves just like Windows” — nothing more, nothing less.

With Microsoft unlikely to (ever) make Windows open source it is left to projects like ReactOS to imagine the “what ifs?”.

Some benefits of ReactOS include:

  • Lightweight (~100MB RAM usage)
  • Wide variety of modules, games and apps available
  • Firefox, OpenOffice & other open source apps available
  • Available to try as a LiveCD

ReactOS 0.4.9: New Features & Significant Changes

ReactOS 0.4.9 builds on the significant improvements featured in its previous release three months back, which saw system notifications and notification tray, shell auto-completion, new NTFS driver, and improved memory usage added (among other things).

ReactOS now supports ZIP extraction
ReactOS now supports ZIP extraction

Sadly there’s nothing quite as substantive in the latest release, as the team notes in the announcement post:

“Much of the visible effort nowadays comes in the form of quality-of-life improvements in how ReactOS functions. At the same time work continues on the underlying systems which provide more subtle improvements such as greater system stability and general consistency.”

What you will find on offer is better overall system stability and improved memory management; the OS now runs ‘chkdsk’ on a drive after a system crash; and memory leaks in the FastFAT driver have been plugged.

Other notable changes:

  • You can now extract ZIP files in the file manager
  • Action options when dragging file/folder to different location
  • New mouse properties dialog in installer
  • Tweaks to the clipboard viewer, log-off dialog, and command prompt shell
  • Sound Mixer redesign is in keeping with Windows
  • Initial work to support USB booting in future releases 

ReactOS continues to expand its software support for NT 6+ (i.e. apps built for Vista, Windows 8, and Windows 10).

Download ReactOS 0.4.9

reactOS screenshot

Want to try ReactOS? You can, but do keep in mind that it is not recommended for daily computing.

You can download the latest release of React OS — version 0.4.9 — from SourceForge or from the ReactOS website (link below).

Download the latest release of ReactOS

Downloads are provided in two flavours: a boot CD (aka ‘install cd’, around 100MB) and a LiveCD (around 80MB).

Should you need help, a wiki page is available with tips on how to install ReactOS.

Joey, why are you writing about ReactOS?

ReactOS is so faithful it even includes this famous Windows feature

Some of you may be wondering why I’m writing about a project that isn’t Ubuntu related, or even Linux related.

While ReactOS has no direct bearing on Ubuntu it is an interesting open source project, one I’m excited by

What can I say? I like to gawp beyond the orange bubble on occasion, and sometimes when I do I get excited by what I see.

So no, ReactOS has no direct bearing on Ubuntu (other than it contributes to the development of WINE) but it is an interesting open source project and being aware of what’s out there in the wider open source ecosystem is a healthy thing (IMO).


ReactOS is by no means a suitable as a drop-in replacement for Windows (so don’t go installing it on your dad’s laptop for japes), and the perpetual ‘alpha’ tag should warn casual computer geeks away.

But for FOSS enthusiasts and fans of alternative OSes in general ReactOS is a compelling curio that’s well worth keeping tabs on.

Have you tried ReactOS? Are you keen to try it now? Let us know below!
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