Troubleshooting and Downloading PC/AT Enhanced PS/2 Keyboard (101/102-Key) Drivers
If you are seeing the "PC/AT Enhanced PS/2 Keyboard (101/102-Key)" entry in your Windows Device Manager with a yellow exclamation mark, or if your vintage mechanical deck has stopped responding, you aren't alone. While PS/2 is an older standard, it remains a favorite for enthusiasts due to its "NKRO" (n-key rollover) capabilities and direct hardware interrupts.
This guide covers how to restore functionality to your 101/102-key keyboard through driver updates and registry fixes. Do You Actually Need to "Download" a Driver?
In 99% of cases, you do not need to go to a third-party website to download a driver for a standard PS/2 keyboard. The driver is built directly into the Windows kernel (i8042prt.sys and kbdclass.sys).
If the keyboard isn't working, it’s usually because the driver is disabled, the registry entry is corrupted, or the hardware port (the purple circular plug) wasn't initialized during boot. How to Update or Reinstall the Driver via Device Manager
Before looking for external files, let Windows reset the connection: pc at enhanced ps 2 keyboard -101 102-key- drivers download
Open Device Manager: Right-click the Start button and select Device Manager.
Locate the Keyboard: Expand the Keyboards section. You should see "PC/AT Enhanced PS/2 Keyboard (101/102-Key)".
Uninstall Device: Right-click it and select Uninstall device.
Restart: PS/2 is not hot-pluggable. You must restart your computer for Windows to redetect the hardware and reinstall the native driver. The "Code 19" or "Code 10" Registry Fix
Sometimes, Windows fails to start the driver because of "UpperFilters" or "LowerFilters" issues in the registry. This is a common fix recommended on forums like Microsoft Support: Press Win + R, type regedit, and hit Enter. Identify the keyboard brand and model (label on
Navigate to: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Class\4d36e96b-e325-11ce-bfc1-08002be10318.
Look for UpperFilters. Its value should be kbdclass. If it says anything else, change it back to kbdclass. Restart your PC. Forcing the Driver Update manually
If Windows labels it as a "Standard PS/2 Keyboard" and you want the specific "Enhanced" designation: Right-click the keyboard in Device Manager > Update driver. Select Browse my computer for drivers.
Select Let me pick from a list of available drivers on my computer. Uncheck Show compatible hardware.
Under (Standard keyboards), select PC/AT Enhanced PS/2 Keyboard (101/102-Key) and click Next. Still Not Working? Check the BIOS 3. Faulty Windows Installation Sometimes
Since PS/2 keyboards are handled at a lower level than USB, check your BIOS/UEFI settings: Ensure PS/2 Port Support is enabled.
If you are using a USB-to-PS/2 adapter, keep in mind that many are "passive" and only work if the keyboard was specifically designed to support both signals. You may need an "active" converter for modern PCs.
For specific legacy hardware support, you can check manufacturer archives like Lenovo Support or HP Customer Support if your keyboard came bundled with an older workstation.
Are you using a native PS/2 port on your motherboard, or are you using a USB adapter?
Sometimes, Windows disables the PS/2 port driver due to registry corruption or malware. In this case, you don't need a keyboard driver; you need to fix the i8042prt.sys (PS/2 port driver) via the Registry Editor or System Restore.