Thanks, Keith — good details. This is a classic case of USB/HID drivers being fine in BIOS/UEFI but failing once Windows loads. Other users with the same symptom (keyboard lights on in BIOS, then go out at the Windows desktop) have resolved it with offline repairs or a System Restore / driver reset.
Because your keyboard/mouse only work in BIOS, the fastest way to repair is from Windows Recovery (WinRE) or from a Windows 10 install USB (you said you have another PC nearby — you’ll need it to make the USB). Below are step‑by‑step options. Start at A and do each step until your devices work; I’ll walk with you if you get stuck.
A — Make a Windows 10 install/repair USB (on the other PC)
- Get an empty USB stick (8 GB+).
- On the other PC download and run Microsoft’s Media Creation Tool and choose “Create installation media (USB flash drive)”. (If you want I can give exact clicks.)
- When finished plug that USB into the Alienware and boot it. Use F12 (or F11 on some Dells) at power-on to open the boot menu and select the USB drive. (Your keyboard works in BIOS so you should be able to select the USB.)
Why: booting the machine from the USB gives you WinPE/WinRE tools where keyboard/mouse typically work, so you can run repairs even though Windows on the internal disk disables them. This approach is recommended in forum threads with the same symptom.
B — Use the install USB to try Startup Repair / System Restore
- Boot from the USB.
- At the Windows Setup screen click “Repair your computer” (bottom left).
- Troubleshoot → Advanced options → Startup Repair. Let it run.
- If Startup Repair doesn’t fix it, return to Advanced options → System Restore (if a restore point exists) and try that. Many users fixed HID problems with a restore.
C — If Repair/Restore don’t help: use Command Prompt from WinRE
- From Advanced options choose Command Prompt.
- Identify the Windows drive letter (WinPE may assign different letters):
- type
diskpart
then list vol
and note the volume letter for the Windows partition, then exit
to leave diskpart.
- Run these checks (replace C: with the letter you found if different):
chkdsk C: /f
dism /image:C:\ /cleanup-image /restorehealth
sfc /scannow /offbootdir=C:\ /offwindir=C:\Windows
These look for & repair corruption in system files and the offline Windows image. Many driver/HID issues are fixed by repairing corrupted system files.
- Reboot and test.
D — If the keyboard still dies after Windows wallpaper appears
- In BIOS turn OFF any “Fast Boot” or “Ultra Fast Boot” options (these sometimes skip USB initialization). Also confirm “USB Legacy Support” is ENABLED (you said you enabled mouse/keyboard already but double‑check).
- Try booting with only one keyboard directly into a rear motherboard USB 2.0 port (not front panel, not GPU ports). Leave other USB devices unplugged. (You already tried ports, but try again after the DISM/SFC run and after disabling fast boot). Forum reports often showed rear ports + repair fixed it.
E — If you can get into WinRE with keyboard working but not full Windows, consider a Repair Install or Reset
- If you can boot the USB and the keyboard works in WinRE but not in the installed Windows, you can:
- Back up your data (I can give copy commands from the Command Prompt), then try Reset this PC → Keep my files, or
- Perform a clean install / in-place reinstall. (In-place reinstall that keeps apps/files requires running Setup.exe from inside Windows; if that’s not possible, the installation USB can still reinstall Windows and you can choose the “keep personal files” option — still plan for a backup.)
F — If you want to try driver cleanup first (advanced)
- If you do manage to boot to Safe Mode or WinRE with keyboard working, uninstall any non‑Microsoft keyboard/mouse drivers and the USB Host Controller entries in Device Manager (HID, xHCI/eHCI). Then reboot so Windows redetects them. This is the usual fix when Windows loads incorrect HID/USB drivers. If you get to Safe Mode later I’ll give exact Device Manager steps.
If none of the above works (or you don’t want to mess with installations yet):
- I can give the exact Media Creation Tool steps, exact Command Prompt commands for finding the right drive and running DISM/SFC, and commands to back up your files to an external USB drive before doing a reset/reinstall. Which would you like to try next? Do you have:
1) The other PC available to make the install USB?
2) A spare USB stick (8 GB+)?
Tell me “Yes — make USB” or “No — can’t make USB” and I’ll give the next exact step.