: Download and install a compatible Java 8 offline installer.
Since the official Mojang launcher is a no-go, you need a community alternative that supports older Java environments and Windows NT 5.1 (XP). minecraft windows xp download
Have an old Compaq running XP with a glowing green “Play” button? Share your build in the comments below (just don’t connect it to the internet)! : Download and install a compatible Java 8 offline installer