A boot device failure can be incredibly frustrating. You press the power button on your computer and instead of your operating system loading like normal, you get an error message saying something like “No boot device found.” What gives? Let’s break down some of the common causes of boot device failures and how to recover from them.
What is a Boot Device?
When you first turn on your computer, it goes through a boot up sequence that loads the operating system into memory. A boot device is the physical storage drive that contains the operating system files that are loaded at boot time.
On a typical computer, the main boot device is usually the primary hard drive that has the main OS installed on it (like Windows or MacOS). But it can also be other kinds of devices like:
- A solid state drive (SSD)
- A USB flash drive
- An optical disc drive containing a bootable CD/DVD
- An external hard drive
- A network drive
At the start of the boot process, the computer’s BIOS or UEFI firmware checks the designated boot order to see which device it should try loading the OS from first. The boot order is the sequence of devices that the computer checks when trying to find an OS to load at startup.
Common Causes of Boot Device Failures
So what are some common reasons why you might encounter a “no boot device found” or “no OS found” type of error on startup?
The boot order is incorrect
As mentioned above, the BIOS checks devices in a specific boot order. If this order gets changed so that the primary hard drive with the OS is no longer first in the sequence, you may get a boot error. Going into your BIOS settings and correcting the boot order can resolve this.
Loose or faulty hardware connections
Boot devices rely on physical connections inside your computer. If a SATA or power cable connected to your primary hard drive becomes loose or damaged, it can interrupt the boot process. Reseating connections or replacing damaged cables may be necessary to restore proper booting.
Hard drive failures
One of the most common hardware causes of boot failures is a dying or dead hard drive. Hard drives eventually wear out and can start developing bad sectors or mechanical issues that prevent them from being read properly on boot up. Replacing a faulty hard drive will resolve the boot issue in this scenario.
Corrupted system files
The system files required to boot into Windows or other operating systems can sometimes become corrupted. This can occur following a failed Windows update, unexpected power loss while files are being written, malware/virus infection, etc. Depending on the extent of the corruption, system file errors may be repairable using the OS recovery tools.
BIOS or firmware problems
In rare cases, a buggy BIOS or UEFI firmware version can also lead to boot problems. Firmware updates from your motherboard or device manufacturer may be able to correct issues caused by flawed BIOS/UEFI.
Partition issues
For the boot loader to find the OS, partitions on the boot drive need to be properly configured. If the boot partition is deleted or otherwise goes missing, it will trigger the “no boot device” error. This can usually be fixed by recreating the necessary partitions.
Incompatible BIOS/UEFI mode
Some systems can switch between legacy BIOS and modern UEFI boot modes. If the OS was installed in UEFI mode but the BIOS is set to legacy mode (or vice versa), it can lead to a confusing “OS not found” situation. Switching to the proper mode for your installed OS will resolve it.
How to Recover from Boot Device Failure
Okay, so now you know some of the main reasons for a computer booting straight to a “no bootable device” or “OS not found” error screen. How do you go about recovering from a failed boot drive and getting your system running again?
Here are some steps to try:
1. Check boot order in BIOS
Enter your BIOS settings on startup and confirm the boot order lists your primary hard drive or SSD first before any other devices. If not, reorder it to give boot priority to the correct drive.
2. Inspect physical connections
Shut down, open the PC case, and check that no SATA power or data cables are loose or obviously faulty. Reconnect any loose cables and replace any damaged ones.
3. Try booting from a USB drive
Create a bootable USB flash drive with a boot utility or OS installer on it. Try booting from the USB drive to see if the primary hard drive is being detected properly.
4. Remove extra internal drives
Disconnect any secondary hard drives or other unnecessary boot devices temporarily to see if it allows booting from the primary drive again. This can isolate the issue.
5. Run hardware diagnostics
Most hard drive manufacturers provide bootable tools to test drive health and scan for defects. Run extended tests and repair any problems found.
6. Attempt OS recovery
If the drive hardware seems okay, try using the Windows recovery environment or other OS recovery tools to repair corrupted system files that may be preventing booting.
7. Replace defective hardware
If all else fails, hardware failure is likely the culprit. Replace any boot drive that is determined to be faulty with a new, compatible replacement.
Best Practices to Avoid Boot Problems
While you can’t prevent every boot device failure, here are some good practices to help avoid them:
- Keep your BIOS/firmware updated to latest stable versions
- Use high-quality, name brand drives from reliable manufacturers
- Don’t overfill drives – leave at least 10-15% free space
- Scan drives regularly for errors and bad sectors
- Make regular backups of critical data
- Use a UPS to safely shut down during power outages
- Always eject and disconnect drives properly rather than just pulling them out
Following best practices for hardware maintenance, drive health, and data backups will give you the best chance of avoiding those panic-inducing “No boot device available” messages!
Recovering Data from a Failed Boot Drive
One concern when dealing with a failed boot drive is recovering your personal data from it. If the drive is failing mechanically or has severe file system corruption, you may not be able to simply mount it as a secondary drive and copy files from it.
In these scenarios, here are a couple options for salvaging your data from the damaged boot drive:
Try a Linux live CD
Booting from a Linux live CD can sometimes allow you to access corrupted filesystems that Windows cannot. Linux has more robust NTFS support and data recovery tools that may enable successfully copying data off a failing drive.
Remove the drive and use recovery software
Another option is to physically remove the damaged drive and connect it as an external drive to another working computer. Specialized data recovery software can then scan the drive and recover retrievable files.
Some popular data recovery programs include:
- EaseUS Data Recovery Wizard
- Stellar Data Recovery
- R-Studio Data Recovery
- Disk Drill
This method raises the chances of a successful data recovery, but minimizes risk of overwriting the drive and losing data permanently.
Send it to a professional recovery service
For difficult mechanical failures or highly corrupted drives, you may want to leave drive recovery up to the pros. Professional data recovery services can disassemble drives in a cleanroom environment and repair or extract the platters as a last resort.
Just be aware that professional recovery services tend to be very expensive, costing hundreds to thousands of dollars in some cases. The value of recovering your lost data will need to justify the cost.
Preventing Data Loss from Boot Drive Failure
While boot drive failures can sometimes be unavoidable, you can take steps to prevent catastrophic data loss when they do occur:
- Have a current drive backup – Maintain regular backups to an external drive or cloud storage.
- Use a RAID array – Configure multiple drives in a fault-tolerant RAID setup.
- Enable drive failure prediction – Modern drives have S.M.A.R.T. monitoring to predict issues.
- Encrypt your data – Use BitLocker or other encryption to secure sensitive data.
- Know your recovery options – Be familiar with recovery methods before you need them.
Planning ahead for potential drive issues can save you from disaster in the event of a sudden boot drive failure.
When to Replace a Failing Boot Drive
If repeated troubleshooting and repairs fails to get an ailing boot drive working properly again, it’s probably time to retire and replace it. But when is the right time to cut your losses and upgrade to a new drive?
Here are some signs that indicate a boot drive is too far gone and needs to be swapped out:
- Frequent boot failures and Blue Screens of Death
- Extremely slow boot up and app loading times
- Drive making unusual clicking or beeping noises
- Bad sectors steadily spreading across the drive
- Difficulty partitioning or inability to format the drive
- Failed drive diagnostics testing
Continuing to use a damaged boot drive that exhibits these types of issues can lead to serious performance and data reliability problems. At that point, it’s best to retire it and start fresh with a new, high-quality drive.
Choosing a Replacement Boot Drive
When selecting a replacement boot drive after a failure, you’ll want to choose one well-suited to your specific needs and budget. Here are some factors to consider:
HDD vs SSD
For optimal system performance, an SSD is highly recommended as a boot drive these days over a traditional hard disk drive (HDD). SSDs have faster boot times, app launching, and data access due to improved mechanical design.
Drive interface
Common modern drive connection interfaces like SATA III and NVMe are designed for maximum bandwidth and speeds. Make sure your motherboard supports the interface required by the new drive.
Drive capacity
Choose a drive capacity adequate for your storage needs, while allowing at least 10-15% free space. Larger drives tend to have better performance and lifespan.
Brand and model reputation
Stick with major brands known for quality drives. Read reviews and benchmarks for the specific model you’re considering to confirm reliable real-world performance.
Warranty
Opt for a drive with at least a 3-5 year warranty from the manufacturer to cover you in case of early failure.
Budget
Factor in how much you can reasonably spend. Faster SSDs and large capacity enterprise HDDs can get pricey. But more affordable options still offer good reliability.
Migrating Your OS to a New Boot Drive
Once you’ve selected a suitable replacement boot drive, you’ll need to migrate your operating system, applications, and data over to it.
There are a few options for transferring your OS installation:
Cloning
Use drive cloning software to do a full 1:1 copy of your original boot drive contents over to the new drive.
Clean install
Wipe the new drive and do a completely fresh OS installation. Then copy your files and reinstall apps.
System image
Restore a system image backup you created previously to instantly replicate your OS setup on the new drive.
The cloning route is quick and easy, but may carry over problems from the old drive. A clean install ensures you start completely fresh. Just be sure to backup your data first!
Verifying Boot Reliability After Drive Replacement
After replacing your boot drive, confirm normal system operation by:
- Booting successfully to the OS multiple times
- Loading apps, saving files, and checking drive speed
- Performing a full antimalware scan
- Monitoring system stability for a few days
- Running extended drive diagnostics overnight
If no further issues arise, you can be confident your boot troubles are resolved. Don’t forget to restore your data backups and remove any old drives no longer needed.
Seeking Professional Repair Service
For difficult to diagnose or catastrophic boot drive failures, seeking professional PC repair may be your best bet for getting back up and running quickly.
Some benefits of taking your PC to a professional repair shop include:
- Experience recovering data from damaged drives
- Ability to test components and isolate faulty hardware
- Access to spare parts for immediate replacement
- Availability of advanced diagnostic tools
- Efficiency in disassembling and repairing devices
- Convenience of shop handling the entire repair process
Just be sure to find a reputable shop with expertise in handling boot drive issues. Confirm upfront pricing and get an estimate time frame for completion. Onsite business support or mobile repair services can also fix issues quickly without you having to haul the PC in.
Conclusion
Dealing with a failed or failing boot drive can certainly be a headache. But understanding common causes like bad hardware connections, drive corruption, failed components, and configuration issues allows you to troubleshoot and resolve many boot problems.
Recovering data from the old drive, replacing with new stable storage, migrating your OS cleanly, and confirming normal operation will get your computer booting happily once again. Don’t hesitate to enlist professional assistance if you encounter tricky scenarios requiring advanced technical expertise.
Sticking to reliable computer hardware, following best practices, and maintaining recent backups will minimize hassles in the event of sudden boot drive failure. But should problems strike, use the strategies outlined here to diagnose causes, recover or replace the drive, and resume productivity.