We would like to inform you of the operating system compatibility of the Steam version of "Touhou Gensou Mahjong" including the DEMO version. We had originally planned to support Windows 7~8,1 for "Touhou Gensou Mahjong", but as of January 1, 2024, the Steam client will only be compatible with Windows 10 or later, However, as of January 1, 2024, the Steam client will only be supported on Windows 10 or later, and "Touhou Gensou Mahjong" will also be supported on Windows 10 or later accordingly. Please note that we may not be able to support operation on operating systems prior to Windows 10.