When your PC fails to start properly, it usually indicates a problem with the boot process, system files, or hardware. This guide covers the most common startup failures and how to fix them in Windows 10 and Windows 11.
Common Startup Symptoms
- PC stuck on manufacturer or Windows logo
- Boot loops (restarts repeatedly)
- Black screen before login
- “No Boot Device” or “Boot Device Not Found” errors
- Preparing Automatic Repair loop
- Windows attempts to load but freezes
Step-by-Step Troubleshooting
Follow these steps in order. Each step is safe for beginners.
1. Check Physical Connections
Loose or failing components can interrupt startup.
- Ensure power cable is secure
- Check internal drive cables (if desktop)
- Disconnect USB devices that may interfere with boot
2. Enter BIOS/UEFI
Incorrect settings can prevent Windows from loading.
- Restart and press the BIOS key (Esc, F2, F10, Del)
- Confirm the boot drive is detected
- Ensure the correct drive is first in Boot Order
- Disable Fast Boot if the system is stuck
3. Run Startup Repair
Windows can automatically fix many startup issues.
- Turn the PC on and off three times to trigger Recovery Mode
- Select Troubleshoot → Advanced options → Startup Repair
4. Repair Boot Files
Corrupted bootloaders can stop Windows from loading.
Open Command Prompt from Recovery Mode and run:
bootrec /fixmbr bootrec /fixboot bootrec /scanos bootrec /rebuildbcd
5. Check the Boot Drive
Failing drives often cause startup failures.
- Listen for clicking or grinding noises (HDD)
- Run from Recovery Mode:
chkdsk C: /f /r
6. Test RAM and CPU Stability
Faulty memory or overheating can interrupt startup.
- Reseat RAM modules
- Test one stick at a time
- Ensure CPU cooler is properly attached
7. Use System Restore (If Available)
Restores Windows to a working state without deleting files.
- Open Recovery Mode
- Select Troubleshoot → Advanced options → System Restore
8. Reset Windows (Last Resort)
If startup issues persist, a reset may be required.
- Go to Recovery Mode
- Select Reset this PC
- Choose Keep my files when possible
Still Having Issues?
If the PC still won’t start, the problem may be hardware‑related. Check:
- Power supply
- Motherboard
- SSD/HDD health
- RAM stability
For deeper troubleshooting, see related guides such as boot repair, drive diagnostics, and hardware testing.