'No bootable device' or the PC beeps when it starts
If your PC shows a message like No bootable device, Operating system not found or Reboot and select proper boot device, or it makes a series of beeps and nothing appears, it cannot find or start Windows. Here is what the usual causes are and what you can safely check.
Check the simple things
- Switch off, then unplug every USB stick, external drive, memory card and disc.
- Switch on again. A forgotten USB stick is a very common cause, because the PC tries to start from it first.
- Make sure the power cable is firmly in and, on a laptop, that the battery is charged.
- Hold the power button for 15 seconds to switch off, wait a minute, then try once more.
What the message means
The PC has looked for Windows on its drive and found nothing it can use. This can be because:
- The drive has failed or become loose. This is serious, and the quicker you stop, the more likely your files can be saved.
- Windows start-up files are damaged. These can often be repaired.
- The PC is set to start from the wrong place. This can happen after a power cut or a flat CMOS battery.
Do not reinstall Windows to fix this, because it can wipe your files.
About beeps
Beep patterns are not the same on every make. A repeated series of beeps at power-on often points to memory (RAM), the graphics card or the motherboard, but the exact meaning is in your manual or on the maker's support site. Write down how many beeps you hear, whether they are long or short, and the make and model.
On a desktop, only reseat memory or cards if you are comfortable doing so: switch off, unplug at the wall, and touch bare metal on the case first. Never open a laptop.
When to get more help
Get in touch as soon as the message appears more than once after the checks above. Do not keep restarting if you hear clicking, or if the PC beeps and stays blank. Tell us the make and model, the exact message or beeps, and whether you have a recent backup.