Never download drivers from "driver update" pop-up ads or unknown executables. Many fake driver sites host malware designed for outdated XP systems that lack modern security patches.
Are you connecting to a specific PLC model like an S7-300 or S7-400? Knowing the hardware helps in choosing the right MPI vs. Profibus PC Adapter USB A2 will not Connect - SiePortal pc adapter usb a2 driver windows xp
Siemens SIMATIC PC Adapter USB A2 6GK1571-0BA00-0AA0 compatible with Windows XP SP2 and higher Never download drivers from "driver update" pop-up ads