Keyboard works in bios not windows

A keyboard usable in firmware but silent after Windows starts points to a later software or driver layer.

Run the check

Confirm the keyboard works in the firmware screen without changing settings.
After Windows starts, compare a second port and another keyboard.
Check Device Manager and accessibility input settings for the affected device.

Read the result

The change at OS startup narrows the fault but does not identify one driver automatically.

Limits and next step

A browser test cannot run inside BIOS or repair Windows drivers.

Repeat the check after changing one setting or connection. Keep a record of what changed before deciding whether the device needs service.