The search for is a journey through the abandoned alleyways of RC simulation history. While it is theoretically possible to get your legal copy of RealFlight 6.5 running on a modern PC with manual patches and offline activation, the experience will be subpar. You will face crashes, missing features, and a ghost town of an online community.
: For those who migrated to the Steam edition in later years, the serial number is automatically handled by your Steam library and does not require manual entry. How to Update or Manage Serial Numbers