using Windows 7 compatibility + Admin .
If you absolutely must use the original SmarThru 4 interface, you need to bypass the Windows driver signature requirements: smarthru 4 samsung scx4521f software download fix top
Samsung sold its printer division to HP in 2017. Official Samsung support pages have been redirected to HP. This causes broken links and confusion for the SCX-4521F series. using Windows 7 compatibility + Admin