A “no bootable device” message on a black screen means your computer has looked for a drive to start Windows (or macOS) from and couldn’t find one. Sometimes that’s a trivial setting; sometimes it’s a failed drive with your files on it. The good news is you can work through it from harmless to serious — here’s what the error means, how to fix it, and how to get your data back if the drive has died.
The error just says the computer found nothing to boot from. That could be the boot order, a loose cable, corrupt Windows files, or a dead drive — so work from the cheap causes up, and treat your data as the priority if the drive itself has failed.
When a PC powers on, its firmware (the BIOS or UEFI) looks through a list of devices for one containing a bootable operating system. “No bootable device” — and its cousins “no boot device available” and “operating system not found” — simply mean that search came up empty. Crucially, that doesn’t automatically mean your drive is dead or your files are lost; it means the computer couldn’t start from the drive. The cause could be as minor as a changed setting or as major as a hardware failure, so the sensible approach is to work through the possibilities from least to most serious.
Start with the cheap fixes. The commonest is boot order: enter the BIOS/UEFI (usually by tapping F2, F12, Delete or Esc at power-on) and check that your main drive is listed and set as the first boot device — a flat CMOS battery, a plugged-in USB stick, or a knocked setting can all bump it down the list. While you’re there, see whether the drive is detected at all. If it’s a desktop, or you’re comfortable inside a laptop, reseating the drive’s power and data cables can fix a connection that’s worked loose. If the drive shows up and the boot order is right but it still won’t boot, the problem has moved from hardware to software.
If the drive is detected but Windows won’t start, the boot files or partition may be corrupt — from a failed update, a power cut during a write, or file-system damage. Windows’ built-in Startup Repair (from a recovery USB) can often rebuild the boot information, and tools like bootrec can repair the boot sector. These are safe to try because the drive is healthy — they fix the software, not the disk. What you should be wary of is any option that reinstalls Windows or wipes the drive to “fix” it: if your files aren’t backed up, that’s the step that loses them. Recover the data first if it matters.
If the BIOS doesn’t detect the drive at all, or the drive is clicking or silent, the hardware has failed — and no boot repair will help. At that point the machine is a secondary concern; the priority is the data. Don’t keep power-cycling the computer hoping it catches, and don’t let anyone reinstall Windows onto a replacement drive before the original is recovered. A failed boot drive is recovered the same way as any dead drive — repaired enough to read on the bench, then imaged read-only — and a single drive is from £300 +VAT. Once the data’s safe, the computer can have a fresh drive and a clean install.
It means the computer looked through its devices for one containing a bootable operating system and found none. It does not automatically mean the drive is dead or your files are lost, only that the machine could not start from the drive. The cause ranges from a changed boot-order setting to a corrupt Windows install to a failed drive.
Work from harmless to serious. Check the BIOS boot order and that your drive is detected and set first; reseat the drive cables on a desktop. If the drive is detected but Windows will not start, try Startup Repair from a recovery USB. If the drive is not detected at all, or is clicking, it has failed, and the priority becomes recovering the data rather than fixing the boot.
Not necessarily. If the cause is the boot order, a cable, or corrupt Windows files, the drive and your data are fine once it is fixed. Your data is only at risk if the drive itself has failed, or if you reinstall Windows or wipe the drive to fix the error without backing up first. Recover the data before doing anything destructive.
Usually a loose or failed cable, or the drive itself having failed, a dead board, a stuck motor, or failing heads. Reseating the cables can fix a connection problem. If the drive still is not detected, or is clicking or silent, the hardware has failed and it needs bench recovery rather than more attempts to boot.
Yes. A drive that will not boot is often still recoverable, sometimes it is only a software or connection fault, and even a physically failed boot drive can be repaired enough to read on the bench and imaged read-only. Stop reinstalling or power-cycling, and a single drive recovery is from 300 pounds plus VAT after a free diagnostic.
If the drive is clicking or the BIOS can’t see it, don’t reinstall over it. Send it in and we’ll recover it read-only first — free diagnostic, fixed quote before any work.