FreeSO is a reimplementation of The Sims Online™’s game engine, using C# and Monogame.
An installer is available that downloads and extracts the The Sims Online™ game files from EA’s official FTP servers (assuming they are available), as well as downloading the latest build of the FreeSO client from ours, which has been built from the ground up to utilise the TSO files. You may need to install the .NET Framework v4.5 before you can run the installer or game if you do not have Windows 10.
