If Windows 11 blocks the installation because the KP206BUB driver is unsigned (very common for legacy hardware), you must temporarily disable driver signature enforcement:
And the Driver? He was a legend.
The "KP" prefix usually denotes a chipset manufactured by a smaller semiconductor firm (often Korean or Chinese in origin) that specializes in USB-to-serial or USB-to-parallel bridge controllers. The "206" refers to the specific model series, while "BUB" typically indicates the (e.g., Bulk-Only Transport with USB Bridge). kp206bub driver