The KSP software uses direct access to the input/output address space of the processor. This software works directly in Windows 98/Millenium environment. The Windows 2000/XP protects i/o addresses against direct access by the sfoftware. In this case it is necessary to use an additional software for removing the protection. Visit the internet page and find more information: http://www.direct-io.com/ and download the file directio.exe (1650 KB). The KSP system uses i/o addresses $100-$1FF and KSP-2 system uses the addresses $3F8-$3FA (printer port LPT1).