1. Build environment To build the system you need either mingw32 installed on Windows or a mingw32 cross compiler running on unix. You may obtain MinGW binaries that build ReactOS from http://www.reactos.com. 2. Building ReactOS 2.1 Building the binaries To build ReactOS run 'make' (wihout the quotes) if you are building on Linux or 'mingw32-make' if you are building on Windows (or ReactOS) from the top directory. 2.2 Building a bootable CD image To build a bootable CD image run 'make bootcd' (wihout the quotes) if you are building on Linux or 'mingw32-make bootcd' if you are building on Windows (or ReactOS) from the top directory. This will create a CD image with a filename, ReactOS.iso, in the top directory. 3. Installation ReactOS can only be installed on a machine that has a FAT16 or FAT32 partition as the active (bootable) partition. The partition on which ReactOS is to be installed (which may or may not be the bootable partition) must also be formatted as FAT16 or FAT32. ReactOS Setup can format the partitions if needed. ReactOS can be installed from the source distribution or from the bootable CD distribution. The two ways to install ReactOS are explained below. 3.1 Installation from sources If you don't have an existing ReactOS installation you want to upgrade, then build a bootable CD as described above. Burn the CD image, boot from it, and follow the instructions to install ReactOS. If you have an existing ReactOS installation you want to upgrade, then to install ReactOS after building it, type 'make install' or 'mingw32-make install'. This will create the directory 'reactos' in the top directory. Copy the contents of this directory over the existing installation. If you don't want to copy the files manually every time you run a 'make install' or 'mingw32-make install', then you can specify the directory where the files are to be copied to during installation. Set the ROS_INSTALL environment variable. If you are on Windows this could be done by: set ROS_INSTALL=c:\reactos If you are on Linux this could be done by: export ROS_INSTALL=/mnt/windows/reactos Now run 'make install' or 'mingw32-make install' to install the files to the new location. 3.2 Installation from bootable CD distribution To install ReactOS from the bootable CD distribution, extract the archive contents. Then burn the CD image, boot from it, and follow instructions. 5. Help If you run into problems or have suggestions for making ReactOS better, please visit the address below and subscribe to one or more of the mailing lists. http://www.reactos.com/en/content/view/full/66 ReactOS Development Team