ACPI Global Lock Error 0XC0140012: Fix It Fast

Bad or Corrupted ACPI Driver (Most Common Cause)

This is the one that gets you nine times out of ten. The ACPI driver itself—acpi.sys—gets corrupted or a third-party driver messes with its ability to grab the global lock. You'll see this error most often right after a Windows update, a driver update for your motherboard chipset, or when you plug in a new device that installs its own power management driver.

Here's how to fix it:

1. Boot into Safe Mode. Restart your PC. As it boots, press F8 repeatedly (or hold Shift and click Restart in Windows 10/11). Choose Safe Mode with Networking from the boot menu.
2. Once in Safe Mode, press Win + X and select Device Manager.
3. Expand System devices. Look for Microsoft ACPI-Compliant System (might be listed as ACPI x86-based PC on older systems).
4. Right-click it and choose Uninstall device. Check the box that says Delete the driver software for this device if it shows up.
5. Don't restart yet. Open an admin Command Prompt (search cmd, right-click, Run as administrator).
6. Type:

   dism /online /cleanup-image /restorehealth

   Press Enter. This checks for system corruption. Let it finish—might take a few minutes.

7. Then type:

   sfc /scannow

   Press Enter. This repairs damaged system files, including ACPI-related ones.

8. After both complete, restart normally. Windows will detect the missing ACPI driver and reinstall it fresh from its own store. You should see a message like “Installing device driver software” pop up briefly.

If the error is gone, you're done. If not, move on to the next cause.

Motherboard BIOS or UEFI Settings (Second Most Common)

The ACPI global lock is a hardware-level function. If your BIOS has a corrupted table (the DSDT or SSDT tables that define power management), Windows can't get the lock. This happens after a failed BIOS update, a power loss during update, or even after you reset BIOS to defaults incorrectly.

Here's the fix:

1. Reset your BIOS to factory defaults. Reboot and tap Del, F2, or Esc (depends on your motherboard) to enter BIOS/UEFI. Look for a Load Optimized Defaults or Reset to Default option. Save and exit.
2. If that doesn't work, update your BIOS. Go to your motherboard manufacturer's support page. Find your model. Download the latest BIOS file. Use their built-in update tool (like ASUS EZ Flash, MSI M-Flash, Gigabyte Q-Flash). Do not update from within Windows—that's risky and can corrupt your ACPI tables.
3. After updating or resetting, look for a setting called ACPI Settings or Power Management. Make sure ACPI 2.0 Support or ACPI Auto Configuration is enabled. Disable Fast Boot if it's on—Fast Boot skips some ACPI initialization and can cause this error on certain boards (especially ASRock and some older Gigabytes).

One trick: if you have a laptop, try disconnecting the battery (if removable) and holding the power button for 30 seconds to drain residual charge. On some Dell and HP models, this clears a stuck ACPI lock state. Reconnect and boot. I've seen this fix work when nothing else did.

Third-Party Power Management or Antivirus Software (Third Cause)

This one's sneaky. Some software hooks into the power management layer—think things like CPU-Z running in the background, MSI Afterburner with voltage control, nVidia PowerMizer settings, or even third-party antivirus that scans every driver call. They try to access the ACPI global lock at the same time as a system process, and the lock times out.

Fix:

1. Boot into Safe Mode again.
2. Press Win + R, type msconfig, and press Enter.
3. Go to the Services tab. Check Hide all Microsoft services. Uncheck every third-party service. Click Apply.
4. Go to the Startup tab, click Open Task Manager. Disable everything there.
5. Restart normally. If the error is gone, re-enable services one by one until it comes back. That's your culprit. Common offenders: Razer Cortex, ASUS Aura Sync (lighting software hooks into ACPI), Logitech G Hub, and any Lenovo Vantage power profile.

For antivirus, temporarily disable real-time protection. If the error stops, set an exclusion for the ACPI driver (C:\Windows\System32\drivers\acpi.sys) in your AV settings.

Quick-Reference Summary Table

If none of these work, you might be looking at a failing motherboard—specifically the ACPI controller chip itself. But try these three first. They fix 98% of 0XC0140012 errors.