→ You downloaded 64-bit but have 32-bit Windows. Download the 32-bit version instead.
Apache OpenOffice is stable but updated infrequently (security fixes only). For cutting-edge 64-bit optimization, consider LibreOffice. openoffice download 64 bit
Apache OpenOffice is currently distributed as a for Windows. It runs seamlessly on 64-bit Windows versions by utilizing the operating system's built-in 32-bit compatibility mode. OpenOffice.org 64 bit for Windows - (View topic) → You downloaded 64-bit but have 32-bit Windows