Laptop Keyboard Single Key Malfunction

Verify if the issue is hardware or software by entering the BIOS/UEFI during startup. If the key fails to register input within the BIOS/UEFI interface, the issue is confirmed as a hardware-level defect. If the key functions within the BIOS but fails in the operating system, the issue is confirmed as software or driver-related. Additionally, testing with an external USB keyboard can isolate whether the failure is limited to the built-in keyboard assembly.

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