I have had to reinstall Windows 10 on my PC where Infix Professional was installed. I reinstalled Infix 6.5 and entered the activiation code, but the Infix Printer driver does not get installed. I can see that the setup program gets copied to some location on my PC during the install process (it's too fast for me to see exactly where), but the Printer setup process never starts, and the Infix printer option is not available in any app.
Please uninstall Infix and then restart Windows 10. Install Infix again and then restart Windows 10 again. Hopefully the Infix Printer should then work.