It was designed to detect a physical "Sentinel" or "HASP" USB dongle.
FlexiSIGN-PRO 8.1 is a legacy sign-making and graphics software developed by SAi (formerly Scanvec Amiable) that is widely used for professional vinyl cutting and large-format printing flexisign pro 81 serial key work
Disclaimer: This information is for educational purposes regarding legacy software usage. Using pirated software is illegal. Problems installing flexisign 8.1 | Signs101.com It was designed to detect a physical "Sentinel"