The minimum requirements to install ReactOS are:
- RAM: at least 64 MB, recommended 256 MB.
- Processor: x86 or x64 architecture, Pentium or later and compatibles; for more information see ReactOS ports.
- HDD: IDE/SATA with minimum 450 MB of free space on the primary partition (please note that some SATA controllers may not work with ReactOS):
- FAT16/FAT32 primary boot partition.
- Video: VGA compatible video card (VESA BIOS version 2.0 or later).
ReactOS has limited hardware support. Lists of hardware that have been tested can be found at the following:
There are several things to be made aware of before installing ReactOS, or even obtaining the installation media. These include how ReactOS will be installed, limitations of the installation, and backing up existing data.
The first consideration to make is whether to install ReactOS on a dedicated testing machine or in a contained environment, such as running on an emulator without direct disk access. The use of an emulator is preferable if the machine on which you will run ReactOS is your primary computer or if you have important data on the computer which you cannot afford to lose.
If you decide to install ReactOS on a disk drive that contains an existing operating system (such as Microsoft Windows XP), you should ensure that the drive is formatted with a file system ReactOS can access and write to (now, primary FAT32/FAT16 partition) and that there is sufficient free space on the drive such that ReactOS can be installed (now, >=450 MB). Furthermore, the current hardware limitations to which ReactOS is constrained must be identified and compared to the target computer system (e.g. that ReactOS has basic USB support as of the 0.3.14 release).
Once the available hardware and software situation is determined the installation media can be selected. For example, if your computer includes an ATA CD-ROM and an IDE hard disk that does not contain irreplaceable data, a good installation option may be to write an ISO image of the ReactOS installation media to a CD-RW and proceed to install ReactOS on the IDE hard disk via the CD-ROM.
The ReactOS setup utility and boot loader have a number of limitations. The most prominent are:
- some SATA controllers may not work with ReactOS.
- the boot partition must be the first FAT16 or FAT32 partition on the disk.
- the setup utility cannot check the integrity of file systems.
- the setup utility does not prevent users from performing dangerous and potentially destructive operations.
Due to the current state of the project, the ReactOS Foundation does not offer official installation media for distribution. Installation CD-ROMs must be created by the user by writing an available image file to a CD-ROM.
Downloading the image file
Official ISO image files can be downloaded at one of the following locations:
Creating the Installation CD
The downloaded file is a compressed archive in ZIP format, containing a single file named "ReactOS.iso". The ISO image contains everything needed to create the CD.
- Extract the image file from the archive into a temporary directory.
- Burn the ISO image to a CD-R or CD-RW using any software of your choice.
When burning the ISO to disc, be sure it is written as an image file. Writing to the disc as another type of data will not work and render the Installation CD unbootable. Look for an option similar to "Burn from ISO" or "Write disk image".
ReactOS goes through three stages during setup. The first two stages deal with the installation of the system, while the third stage is the first usable boot by the user.
- First stage – Text mode setup, started when booting from a ReactOS CD-ROM.
- Second stage – Booting to GUI installer. Input of user information and registering of files.
- Third stage – Booting to desktop, user configurations.
- Make sure your BIOS is configured to boot from the CD-ROM first.
- Insert the ReactOS setup CD-ROM into a CD-ROM drive and reboot your computer. On the next boot, the ReactOS setup utility will start.
- Follow the instructions on the screen to install ReactOS on your computer.
- After the installation has finished, remove the setup CD-ROM from the CD-ROM drive and press Enter to reboot your computer. You can now start ReactOS by selecting it from the boot menu.
Due to problems with the USB stack it is NOT currently possible to install ReactOS from a USB stick or USB CD-ROM, the setup process will fail partway through. This worked previously but was broken several years ago by a rewrite of the USB code. See the LiveUSB page for more details, or watch this video-tutorial for different installation method: https://youtu.be/eancDwmWyCw
A Virtual Machine is a software program that provides a virtual hardware platform. Software instructions that would be run on hardware are now interpreted by the emulator software. This allows you to "run" a different kind of computer hardware and its software in a window on your computer.
- VirtualBox – a free virtualization software for Windows, Linux and Mac (HOWTO)
- QEMU – an open source machine emulator