RealVNC offline keys are single-use. If you try to re-use the same .rlf file on a second PC, it will be rejected. Fix: You need one unique offline key per physical or virtual machine. Return to the portal and generate a separate key for each endpoint.
If you try to use a 3-year-old offline key on a fresh install of Windows 11, you will see: realvnc offline license key new
A RealVNC offline license key is a unique code that allows users to activate their RealVNC software for offline use. When a user purchases a RealVNC license, they receive a license key that must be activated online. However, for users who don't have a stable internet connection, an offline license key is necessary. This key enables users to activate their RealVNC software without an internet connection, ensuring seamless remote access. RealVNC offline keys are single-use