STATUS_ACPI_INVALID_TARGETTYPE (0xC014000A) Fix

#1 Fix: Revert or Update the BIOS/UEFI

This error almost always shows up right after you update your motherboard's BIOS or UEFI firmware. I've seen it on Dell Optiplex 7080s and custom ASUS Z490 builds. The new BIOS expects a different ACPI table structure than what your current Windows installation has stored.

1. Restart your PC and press the key to enter BIOS setup (usually Del, F2, or F12).
2. Look for a section called "Save & Exit" or "Boot".
3. Find the option to "Load Optimized Defaults" or "Load Setup Defaults".
4. Press Enter on it, then confirm with Yes.
5. Save and exit. Your PC will restart.

After doing this, Windows should boot normally. If the error comes back, you need to roll back the BIOS version. Go to your motherboard manufacturer's support site, download the older BIOS file you had before, and flash it back using their tool (like ASUS EZ Flash or MSI Flashback).

Expected outcome: After loading defaults, Windows boots without the error. You may see a message saying "BIOS settings have been reset". That's normal.

#2 Fix: Disable or Update ACPI-Critical Drivers

If the BIOS reset didn't work, the problem is likely a driver that conflicts with the ACPI controller. The most common culprit is the Intel Management Engine Interface (MEI) driver, but also check any chipset drivers you installed recently.

1. Press Windows + X and select "Device Manager".
2. Expand "System devices".
3. Look for entries named "Intel Management Engine" or "High Precision Event Timer" or "ACPI x64-based PC".
4. Right-click each one and select "Update driver" → "Browse my computer for drivers" → "Let me pick from a list".
5. Choose the generic Microsoft driver (like "Microsoft ACPI-Compliant System") if available. Otherwise, undo that change.

If updating doesn't help, uninstall the driver completely. Right-click the device, select "Uninstall device", check "Delete the driver software for this device", then confirm. Reboot immediately. Windows will reinstall the generic driver on restart.

Expected outcome: After uninstalling the driver and rebooting, you should see Windows reinstall a basic driver. The error disappears if it was a bad driver causing the type mismatch.

#3 Fix: Run SFC and DISM to Fix Corrupted System Files

Sometimes the ACPI error isn't from your hardware but from corrupted system files. This happens after a failed Windows update or a disk error. I had a user whose laptop got the error after a power cut during a Windows 11 22H2 update.

1. Open Command Prompt as admin: press Windows + X, select "Terminal (Admin)" or "Command Prompt (Admin)".
2. Type sfc /scannow and press Enter.
3. Wait for the scan to finish. It takes 10-15 minutes. Don't close the window.
4. After SFC finishes, type DISM /Online /Cleanup-Image /RestoreHealth and press Enter.
5. DISM runs another 15-20 minutes. Let it finish completely.
6. Restart your PC.

Expected outcome: SFC may say "Windows Resource Protection found corrupt files and successfully repaired them." DISM should say "The restoration operation completed successfully." The error should be gone after the restart.

Quick-Reference Summary Table

Start with the BIOS fix—that's the most common trigger for this error. If it's not that, move to drivers. If still no luck, run the system file checks. Don't waste time reinstalling Windows unless all three fail.