Computer Blue Screen on Startup Windows 10: Complete Fix Guide (BSOD at Boot)

Understanding the Windows 10 Blue Screen on Startup

A Blue Screen of Death (BSOD) at startup means Windows 10 encountered a fatal kernel-level error it cannot recover from automatically. The screen displays a stop code (e.g., CRITICAL_PROCESS_DIED, INACCESSIBLE_BOOT_DEVICE) and a QR code linking to Microsoft's BSOD documentation. On Dell computers, these BSODs are especially common after BIOS firmware updates, Intel ME driver updates, or Realtek audio driver conflicts. On new computers, the culprit is often an out-of-box driver incompatibility or a factory Windows image issue.

Common BSOD stop codes and their typical causes:

• INACCESSIBLE_BOOT_DEVICE — storage driver failure, corrupt partition table, or SATA/NVMe mode mismatch in BIOS
• CRITICAL_PROCESS_DIED — a core Windows process (lsass.exe, smss.exe) crashed due to corruption
• MEMORY_MANAGEMENT — RAM errors or paging file corruption
• DRIVER_IRQL_NOT_LESS_OR_EQUAL — a driver accessed memory at the wrong IRQL level
• PAGE_FAULT_IN_NONPAGED_AREA — driver or kernel tried to access non-present memory page
• WHEA_UNCORRECTABLE_ERROR — hardware-level CPU or memory error
• SYSTEM_THREAD_EXCEPTION_NOT_HANDLED — a system thread threw an unhandled exception, often from a third-party driver

Step 1: Record the Stop Code and Access Recovery Environment

Read the stop code. When the BSOD appears, note the exact error string under "What failed" (e.g., ntfs.sys, dxgkrnl.sys). This file name narrows the culprit to a specific subsystem.

Force Windows into the Recovery Environment (WinRE). If Windows cannot boot after two consecutive failures, it opens Automatic Repair automatically. If it does not:

1. Power off the computer by holding the power button.
2. Power it on, and as soon as you see the Windows logo, power it off again.
3. Repeat this hard-reset cycle three times.
4. On the fourth boot, Windows will enter the Automatic Repair / Recovery Environment screen.
5. Click Advanced options → Troubleshoot → Advanced options.

Dell-specific tip: On Dell desktops and laptops, press F8 or F12 at the Dell splash screen to access the Boot Menu and select Windows Recovery Environment directly. Some Dell models require holding Fn + F8.

Step 2: Boot into Safe Mode

From the WinRE Advanced Options:

1. Select Startup Settings → Restart.
2. After the restart, press 4 or F4 for Safe Mode, or 5/F5 for Safe Mode with Networking.

In Safe Mode, Windows loads only minimal drivers. If the BSOD disappears in Safe Mode, the cause is almost certainly a driver or startup program.

Step 3: Check Windows Event Viewer and Minidump Files

Once in Safe Mode (or after booting normally if possible), analyze crash logs:

Event Viewer path: Windows Logs → System (filter for Critical/Error events near crash time)
Minidump location: C:\Windows\Minidump\

Use Windows Debugger (WinDbg) or the free WhoCrashed utility to analyze .dmp files and identify the offending driver or module.

Step 4: Uninstall or Roll Back Recent Drivers

If the BSOD started after a Windows Update or driver installation:

1. In Safe Mode, open Device Manager (right-click Start → Device Manager).
2. Look for devices with a yellow exclamation mark.
3. Right-click the suspect device → Properties → Driver tab → Roll Back Driver.
4. For display drivers (common on new PCs and Dell gaming laptops), right-click the GPU under Display adapters and roll back or uninstall the driver entirely, then restart normally and let Windows install a generic version.

To prevent Windows Update from reinstalling a bad driver, use the "Show or Hide Updates" troubleshooter from Microsoft (KB3073930) or run:

sc config wuauserv start= disabled

(Re-enable after driver is stable.)

Step 5: Run System File Checker and DISM

Corrupted system files are a top cause of CRITICAL_PROCESS_DIED and PAGE_FAULT_IN_NONPAGED_AREA. From an elevated Command Prompt (in Safe Mode or WinRE → Command Prompt):

# Step 1: Run System File Checker
sfc /scannow

# Step 2: If SFC reports errors it cannot fix, run DISM to repair the Windows image
DISM /Online /Cleanup-Image /CheckHealth
DISM /Online /Cleanup-Image /ScanHealth
DISM /Online /Cleanup-Image /RestoreHealth

# Step 3: Run SFC again after DISM completes
sfc /scannow

The SFC log is saved at C:\Windows\Logs\CBS\CBS.log. Search for "cannot repair" to find files that need manual replacement.

Step 6: Run CHKDSK to Check Disk Health

For INACCESSIBLE_BOOT_DEVICE or UNMOUNTABLE_BOOT_VOLUME, the file system or disk itself may be damaged. From the WinRE Command Prompt:

# Check and repair the C: drive (replace C: with your Windows drive letter)
chkdsk C: /f /r /x

# If the drive is locked (it usually is for C:), schedule for next boot
# Type Y when prompted, then restart

For NVMe/SSD drives, also run the manufacturer's diagnostic (Samsung Magician, Intel MAS, Dell SupportAssist) to check for bad sectors or pending reallocations.

Step 7: Test RAM with Windows Memory Diagnostic

MEMORY_MANAGEMENT and WHEA_UNCORRECTABLE_ERROR often point to defective RAM. From WinRE:

1. Go to Troubleshoot → Advanced options → Windows Memory Diagnostic.
2. Choose Restart now and check for problems.
3. After the test, Windows boots and logs results in Event Viewer under Windows Logs → System, source: MemoryDiagnostics-Results.

For more thorough testing, boot MemTest86 (free, bootable USB) and run at least two full passes. Any errors = RAM or slot is faulty.

Dell desktops and laptops have built-in hardware diagnostics: power on and press F12, then select Diagnostics to run the Pre-Boot System Assessment (PSA/ePSA).

Step 8: Rebuild BCD and Repair MBR (for INACCESSIBLE_BOOT_DEVICE)

If the Boot Configuration Database is corrupt, Windows cannot find its boot files. From WinRE Command Prompt:

# Repair the Master Boot Record
bootrec /fixmbr

# Repair the Boot Sector
bootrec /fixboot

# Scan for Windows installations and add to BCD
bootrec /scanos
bootrec /rebuildbcd

# Rebuild BCD store completely (if above fails)
bcdedit /export C:\BCD_Backup
attrib C:\boot\bcd -h -r -s
ren C:\boot\bcd bcd.old
bootrec /rebuildbcd

Step 9: Use System Restore

If you have restore points enabled:

1. In WinRE → Troubleshoot → Advanced options → System Restore.
2. Select the most recent restore point before BSODs started.
3. Confirm and let the restore complete.

Step 10: Last Resort — Reset or Reinstall Windows 10

If all steps above fail:

• Reset This PC (Keep my files): WinRE → Troubleshoot → Reset this PC → Keep my files. Reinstalls Windows but preserves personal data.
• Clean Install: Download the Windows 10 Media Creation Tool from Microsoft, create a bootable USB, and perform a fresh install. Back up data first using Linux Live USB if the system cannot boot.

New computer tip: If the PC is brand new and BSODs appear out of the box, contact the manufacturer (Dell Support, HP Support, etc.) for an RMA or warranty replacement — factory-installed Windows images can occasionally be corrupt.