If your PC shows No Boot Device Found, No Bootable Device, Boot Device Not Found, or a similar message before Windows starts, the computer's firmware cannot find a valid operating system to boot.
The cause may be as simple as an incorrect boot order, but it can also involve a missing Windows Boot Manager entry, changed BIOS/UEFI settings, corrupted startup files, or a failing SSD or hard drive.
Quick answer: Disconnect unnecessary USB drives, enter BIOS/UEFI and check whether your Windows SSD is detected. If the drive is missing, run the PC manufacturer's storage diagnostics before attempting Windows repairs. If the drive is detected, make sure Windows Boot Manager is the normal boot option, then use Windows Recovery Environment > Startup Repair. Do not randomly switch between UEFI and Legacy mode, disable Secure Boot, or erase partitions.
What Does No Boot Device Found Mean?
This message usually appears before Windows itself has loaded.
Your PC's BIOS or UEFI firmware looks through its available storage devices for something it can start. If it cannot find a valid boot entry or operating system, it may display messages such as:
- No Boot Device Found
- No Bootable Device
- Boot Device Not Found
- No Boot Device Available
- Reboot and Select Proper Boot Device
- Operating System Not Found
The wording varies by manufacturer.
The important question is whether the firmware can still see your SSD or hard drive.
| What You Find | Likely Area to Investigate |
|---|---|
| SSD is not detected in BIOS | Drive connection, SSD failure, storage controller or hardware |
| SSD is detected but Windows Boot Manager is missing | Boot configuration or EFI boot files |
| Windows Boot Manager exists but will not start | Windows startup files or system corruption |
| Error began after BIOS update | Firmware settings may have changed |
| Error began after installing another SSD | Boot order or boot entry may have changed |
| Drive fails hardware diagnostics | Possible SSD or hard drive failure |
Disconnect USB Drives and External Storage
Start with the easiest check.
Turn the computer off and disconnect unnecessary external storage, including:
- USB flash drives
- External hard drives and SSDs
- SD cards
- Bootable installation USB drives
- USB docks containing storage
Leave the keyboard and mouse connected if needed, then start the computer again.
If the PC was trying to boot from removable media instead of the internal Windows drive, it may now start normally.
If the error remains, continue to BIOS or UEFI.
Open BIOS or UEFI
The key used to open BIOS or UEFI depends on the PC manufacturer.
Common startup keys include:
- F2
- F10
- F12
- Esc
- Delete
Start pressing the appropriate key immediately after turning the PC on.
If you are unsure, check the support page or manual for your exact laptop or motherboard model.
Once inside BIOS/UEFI, avoid changing several settings at once. First, simply check whether the internal Windows drive is visible.
Check Whether the SSD or Hard Drive Is Detected
Look for a section named something similar to:
- Storage
- NVMe Configuration
- System Information
- Drives
- SATA Information
- Boot
Look for your internal SSD or hard drive.
If the drive appears
This is a useful sign. It means the firmware can at least communicate with the storage device.
The problem may instead involve:
- Boot order
- Windows Boot Manager
- UEFI configuration
- Boot files
- A damaged Windows installation
Continue to the boot-order section below.
If the drive does not appear
Do not begin running Windows boot repair commands yet.
If BIOS cannot detect the drive itself, Windows Startup Repair cannot fix a physically missing or failed SSD.
If the SSD Is Not Detected in BIOS
A drive that disappears from BIOS is more concerning than a simple missing Windows Boot Manager entry.
First completely shut down the computer and start it again.
If the drive remains missing, run the manufacturer's built-in hardware diagnostics if available.
For example, Dell provides pre-boot diagnostics that can test the storage hardware, and HP recommends its UEFI storage diagnostics for Boot Device Not Found errors. :contentReference[oaicite:2]{index=2}
Desktop PCs
If you have a desktop and are comfortable working inside it, a SATA drive may have a loose data or power connection.
Turn the PC completely off, disconnect power, and follow your manufacturer or motherboard documentation before opening the case.
NVMe SSDs use a motherboard slot rather than SATA cables, so troubleshooting is different.
Laptops
Do not disassemble a laptop merely because the SSD is missing from BIOS unless the manufacturer specifically provides a user-service procedure and you are comfortable performing it.
For an in-warranty device, manufacturer diagnostics and support are usually a better next step.
If the SSD appears and disappears
An SSD that intermittently vanishes from BIOS can indicate:
- A poor physical connection
- An SSD controller problem
- A motherboard or slot problem
- Firmware or storage-controller issues
- A failing drive
Back up important data as soon as possible if the PC becomes bootable again.
Check Windows Boot Manager and Boot Order
If your SSD is visible in BIOS, check the boot order.
On a typical modern Windows installation, you may see an entry called:
Windows Boot Manager
That is usually more important than simply placing the raw SSD model name first.
If Windows Boot Manager is available:
- Move Windows Boot Manager to the normal first boot position.
- Save the changes.
- Exit BIOS/UEFI.
- Restart the PC.
If the computer starts, the boot-order change solved the problem.
If the SSD is detected but Windows Boot Manager is missing, move on to Windows recovery tools.
Check UEFI, Legacy and CSM Carefully
Do not blindly switch between UEFI, Legacy BIOS, and CSM because an online guide tells you to.
The boot mode must match how Windows was installed.
Modern Windows 11 systems normally use UEFI. Microsoft also requires UEFI firmware capability for Windows 11 system requirements.
Some newer PCs are designed specifically for UEFI boot. Dell, for example, documents newer systems where selecting Legacy mode can produce a No Boot Device Found error. :contentReference[oaicite:3]{index=3}
If the problem started after a BIOS update
A firmware update can sometimes reset boot-related settings.
If you know the system previously used UEFI and BIOS has changed to Legacy or CSM, restoring the previous known configuration may fix the problem.
If you do not know what the original setting was, use the PC manufacturer's documentation rather than experimenting with random combinations.
Should You Disable Secure Boot?
Do not disable Secure Boot as a routine No Boot Device fix.
Secure Boot is an important UEFI security feature, and changing firmware security settings can also trigger BitLocker recovery on encrypted systems.
If the problem began immediately after someone manually changed Secure Boot settings, restoring the previous known configuration may be appropriate.
Otherwise, leave Secure Boot at the manufacturer's normal Windows configuration unless official troubleshooting for your exact PC tells you to change it.
This is safer than the old advice of disabling Secure Boot simply to see whether Windows starts.
Be Careful With AHCI, RAID and VMD Settings
Some BIOS menus contain storage options such as:
- AHCI
- RAID
- Intel RST
- VMD
Do not switch these randomly.
Windows may have been installed using a specific storage-controller mode. Changing it can prevent Windows from accessing the system drive even when the SSD itself is healthy.
If the error started immediately after a BIOS reset or firmware update and you know the previous storage mode, restoring that original setting may help.
If you do not know the correct setting, check the manufacturer documentation for your exact model.
Open Windows Recovery Environment
If BIOS detects the SSD and the firmware configuration looks correct, the next step is Windows Recovery Environment, also called Windows RE or WinRE.
Microsoft says Windows RE can automatically appear after repeated startup failures. It includes Startup Repair, System Restore, Uninstall Updates, Command Prompt and other recovery tools. :contentReference[oaicite:4]{index=4}
If Windows RE appears automatically
Select:
Advanced options > Troubleshoot > Advanced options
If Windows RE never appears
You can create Windows installation media using another working PC.
Microsoft currently requires a blank USB flash drive of at least 8 GB for its standard Windows installation-media process. The USB is erased when the media is created. :contentReference[oaicite:5]{index=5}
Boot the affected PC from that USB and choose the repair option rather than beginning a clean installation.
Microsoft documents this route as:
Windows Setup > Repair my PC > Windows Recovery Environment
Run Startup Repair
Startup Repair should be the first Windows-level repair tool for a drive that is detected but will not boot.
In Windows RE, select:
Troubleshoot > Advanced options > Startup Repair
Microsoft says Startup Repair can automatically diagnose and repair startup problems including:
- Missing or damaged system files
- Corrupted Boot Configuration Data
- Boot-record problems
- Registry-related startup problems
- Certain incompatible drivers
Allow the process to finish, then restart the PC. :contentReference[oaicite:6]{index=6}
If Startup Repair works, avoid making additional BIOS changes afterward.
If the Error Started After an Update
If Windows boot failure began immediately after a Windows update and the SSD is still detected, Windows RE provides additional recovery options.
Open:
Troubleshoot > Advanced options
Depending on the system, you may see:
- Uninstall Updates
- System Restore
- Startup Repair
Microsoft currently recommends Startup Repair when Windows does not start, and System Restore can also be used from Windows RE when Startup Repair does not solve the problem. :contentReference[oaicite:7]{index=7}
System Restore rolls back system configuration to an earlier restore point without intentionally deleting personal files, although recently installed software or drivers may be affected.
Be Ready for a BitLocker Recovery Key
Some Windows recovery operations or firmware changes may ask for a BitLocker recovery key.
The recovery key is a 48-digit number used to unlock an encrypted Windows drive.
Microsoft notes that a hardware or security change can trigger BitLocker recovery. :contentReference[oaicite:8]{index=8}
Before making major firmware changes, it is a good idea to confirm that you can access your recovery key.
Possible locations include:
- Your Microsoft account
- A work or school account
- A printed copy
- A USB drive where the key was saved
- Your organization's IT department
Important: Microsoft Support cannot recreate a lost BitLocker recovery key.
Repair Windows Boot Files
If Startup Repair fails but the SSD is healthy and Windows is still present on the drive, damaged boot files may need manual repair.
This is where many older tutorials immediately provide:
bootrec /fixmbr
bootrec /fixboot
bootrec /rebuildbcd
That advice is too generic for modern PCs.
Most current Windows 11 computers use UEFI and an EFI System Partition, so the correct repair depends on the actual disk layout and firmware mode.
Microsoft provides the BCDBoot tool specifically for setting up or repairing Windows boot files and the system partition. :contentReference[oaicite:9]{index=9}
However, manually selecting or modifying EFI partitions is an advanced repair because drive letters shown inside Windows RE may not match the letters you normally see in Windows.
Do not format, delete, clean or recreate partitions simply because a generic tutorial tells you to.
If Startup Repair fails and you are not comfortable identifying the correct Windows and EFI partitions, use Microsoft support, your PC manufacturer, or a qualified technician rather than risking your data.
Run SSD or Hard Drive Diagnostics
If No Boot Device Found keeps returning, especially when the drive sometimes disappears from BIOS, run the computer manufacturer's pre-boot storage diagnostics.
Dell
On many Dell systems, the pre-boot diagnostics are available from the F12 boot menu.
Dell recommends its pre-boot hardware diagnostics when a PC cannot boot and may have a storage problem. :contentReference[oaicite:10]{index=10}
HP
HP recommends testing the drive with HP PC Hardware Diagnostics UEFI when a 3F0 Boot Device Not Found error appears. :contentReference[oaicite:11]{index=11}
Other manufacturers
Lenovo, Acer, ASUS, MSI and other manufacturers may provide their own built-in or bootable diagnostics.
Use the manufacturer's official documentation for your model.
If diagnostics fail
A failed storage diagnostic is a strong indication that the drive may need replacement.
If important files are stored on the drive and are not backed up, consider data recovery before performing repeated write operations or reinstalling Windows.
No Boot Device After Installing a New SSD
If the error appeared after installing a new SSD, first ask whether Windows is actually installed on that drive.
A brand-new blank SSD is not bootable by itself.
If you replaced the old system drive with an empty SSD, you must either:
- Restore a system image or properly cloned installation, or
- Install Windows on the new drive
If you added a second SSD while keeping the original Windows drive:
- Enter BIOS/UEFI.
- Make sure the original Windows drive is still detected.
- Check that Windows Boot Manager for the original installation remains the normal boot option.
Installing additional storage can sometimes change boot priority.
When to Reinstall Windows
Reinstalling Windows should come after hardware detection, boot-order checks and recovery tools—not before them.
Microsoft currently recommends installation media when Windows will not start and other recovery options are unsuccessful. :contentReference[oaicite:12]{index=12}
Warning: A clean installation can remove personal files, apps, settings and manufacturer customizations.
Microsoft explicitly describes a clean install as an advanced option and warns that personal data can be removed. :contentReference[oaicite:13]{index=13}
Do not begin deleting Windows partitions during Setup until you are certain important data is backed up or no longer needed.
What to Do If Important Files Are on the Drive
If your SSD or hard drive may be failing and contains files that exist nowhere else, preserving the data should become the priority.
Avoid:
- Repeated clean-install attempts
- Formatting the drive
- Running DiskPart Clean
- Deleting partitions
- Writing large amounts of new data to the drive
If the drive intermittently becomes accessible, copy important files to another drive as soon as possible.
If it is physically failing or cannot be detected reliably, a professional data-recovery service may be safer than repeated repair attempts.
Frequently Asked Questions
Why does my PC say No Boot Device Found?
The BIOS or UEFI firmware cannot find a valid operating system to start. The cause may be incorrect boot order, changed firmware settings, missing boot files or a storage-drive problem.
Does No Boot Device Found mean my SSD is dead?
Not always. If the SSD still appears reliably in BIOS and passes diagnostics, the issue may be boot configuration rather than hardware failure. A drive that is missing or repeatedly disappears from BIOS is more concerning.
What should be first in boot order?
On most modern Windows installations, Windows Boot Manager should normally be the boot entry used for the installed Windows system.
Why is my SSD detected but not bootable?
The firmware may see the physical SSD but not find valid Windows boot files or a usable Windows Boot Manager entry. Startup Repair is a good first recovery step.
Should I switch from UEFI to Legacy mode?
Not randomly. The firmware mode must match the Windows installation. Modern Windows 11 PCs normally use UEFI, and some newer systems do not support booting Windows normally in Legacy mode.
Should I disable Secure Boot?
Not as a routine fix. Secure Boot is an important security feature, and changing it can also trigger BitLocker recovery. Restore previous known settings only when there is a specific reason.
Can a BIOS update cause No Boot Device Found?
It can if the update resets boot order, UEFI mode, storage-controller settings or other firmware configuration. Check the manufacturer's documentation and restore known previous settings rather than experimenting randomly.
What is Windows Boot Manager?
Windows Boot Manager is the firmware boot entry that points the system toward the Windows boot environment on a modern UEFI installation.
Can Startup Repair fix No Boot Device Found?
If the SSD is detected and the problem involves Windows boot files or boot configuration, Startup Repair may fix it. It cannot repair a physically failed or undetected SSD.
How do I get into Windows Recovery Environment?
Windows may enter it automatically after repeated failed startups. You can also boot from official Windows installation media and select the repair option.
Why am I being asked for a BitLocker recovery key?
BitLocker may request its recovery key after certain hardware, firmware or security changes. The key is normally stored in the Microsoft account or organization associated with the encrypted PC.
Should I use bootrec commands?
Do not blindly run a copied set of commands. Modern Windows 11 systems commonly use UEFI and EFI boot partitions, so the correct repair depends on the disk layout. Startup Repair should be tried first.
What is BCDBoot?
BCDBoot is a Microsoft command-line tool used to create or repair Windows boot files and configure the system partition. It is primarily useful for advanced boot repair.
Can installing another SSD cause the problem?
Yes. Adding or replacing storage can change boot order or remove the original boot device from the preferred boot list. Check that the original Windows Boot Manager remains selected.
Why does my HP say Boot Device Not Found 3F0?
HP's 3F0 message indicates that the system cannot find a bootable storage device. HP recommends running its UEFI hard-drive or SSD diagnostics as part of troubleshooting.
Will reinstalling Windows fix the problem?
It can fix a damaged Windows installation when the SSD is healthy, but it will not repair a failed drive. Reinstallation should be a later step because a clean install may erase data.
What if the PC boots again after restarting?
If the error has happened more than once, do not ignore it. Back up important files and check the drive with manufacturer diagnostics, especially if the SSD has ever disappeared from BIOS.
Is Windows 10 still supported?
Microsoft ended standard support for Windows 10 on October 14, 2025. A Windows 10 PC can still run, but Microsoft recommends moving to a supported Windows version when the hardware is eligible.
Final Thoughts
If your PC shows No Boot Device Found, start by determining whether the SSD or hard drive is actually visible in BIOS or UEFI.
If the drive is missing, focus on hardware detection and manufacturer diagnostics. If the drive is detected, check Windows Boot Manager and the boot order before moving into Windows Recovery Environment.
Use Startup Repair before manual boot commands. Avoid randomly changing UEFI, Legacy, Secure Boot, AHCI, RAID or VMD settings because those changes can create additional boot problems or trigger BitLocker recovery.
If the drive fails diagnostics or repeatedly disappears from BIOS, protect your data and treat the issue as a possible storage-hardware failure. A clean Windows installation should remain a last step after safer recovery options have been exhausted.