1. Update BIOS Firmware
- Enter BIOS/UEFI during boot (usually Del or F2).
- Note your current version, then visit the manufacturer’s website.
- Download and apply the latest BIOS update to improve processor compatibility.
2. Check BIOS CPU Settings
While in BIOS/UEFI:
- Disable “CPU Core Control” or “CPU Affinity” if enabled.
- Enable “SMP,” “Hyper-Threading,” or “Multi-Core Support.”
- Restore BIOS to defaults if unsure.
- Save changes and reboot.
3. Boot with One Core (Temporary Workaround)
Press F8 or Shift + F8 (if supported) during boot.
- Choose Advanced Boot Options → Select Safe Mode.
- Once in Safe Mode, limit CPU usage:
- Open msconfig → Boot tab → Advanced options
- Check Number of processors → Select 1 → Apply
- Reboot normally and observe system stability
4. Run System File Checker and DISM
- Open Command Prompt as Administrator:
sfc /scannow
- Then:
DISM /Online /Cleanup-Image /RestoreHealth
- These commands help repair critical boot files and kernel-level components.
5. Adjust VM or Hypervisor Processor Settings
If using a virtual machine:
- Shut down VM → Edit settings → Reduce CPU core count
- Use even processor numbers and enable virtualisation extensions
- Ensure compatibility with the host CPU topology
- Restart and test for recurrence of the BSOD.
6. Perform System Restore
If this BSOD started after a recent change:
- Go to Control Panel → Recovery → Open System Restore.
- Choose a restore point before the error began.
- Follow on-screen prompts to restore system stability.
7. Upgrade Windows
- Ensure your Windows version supports SMP and multiple processors.
- For older systems, consider upgrading to a version that fully supports your CPU architecture.
Final Thoughts
The 0x0000003E MULTIPROCESSOR_CONFIGURATION_NOT_SUPPORTED error reflects a system failure to initialise or manage multiple processors during startup—typically caused by BIOS, VM, or OS-level configuration issues.
To fix it:
- Update BIOS and chipset firmware,
- Adjust CPU-related settings in BIOS or hypervisors,
- And verify OS compatibility with multi-core CPUs.
If none of these steps resolve the issue, consider:
Running a hardware-level CPU diagnostic from your system vendor,
Or performing a clean installation of Windows to remove underlying misconfigurations.