For modern versions of RealVNC (v6.x and v7.x), "keys" have largely been replaced by cloud-based subscriptions Where is my license key? - RealVNC
Even if you find a working key today, it may stop working tomorrow. VNC Connect licenses call home to RealVNC’s servers. A forced disconnect in the middle of a critical remote session due to license revocation could be catastrophic for a business. vnc server license key github hot