If you downloaded an old Windows 7/8 driver and Windows 10 blocks it:

: Right-click the device and select Update driver . Choose Search automatically for updated driver software to let Windows find the latest WHQL-certified driver from its database. Troubleshooting Common Issues USB 2.0 vs. 3.0 Comparison - Verizon

Leo pressed the button on the blue switch. Switched to the work laptop. Keyboard worked. Switched back to the PC. Tablet worked.

In many cases, you don't. Standard manual USB 2.0 switches—those with a physical button to toggle between computers—typically use that are built directly into Windows 10. If your switch has a physical button and isn't working, try these steps first:

These software solutions are useful if your physical USB switch is defective or genuinely lacks Windows 10 drivers.