Opcom 1.99 drivers are essential for the proper functioning of the Opcom 1.99 software on a Windows 10 operating system. The drivers act as a bridge between the Opcom 1.99 software and the vehicle's diagnostic equipment, allowing the software to communicate with the vehicle's systems. Without the correct drivers, the Opcom 1.99 software will not be able to connect to the vehicle's systems, rendering it useless.