Your computer was working yesterday. Today it sits on the manufacturer’s logo for minutes, the BIOS crawls through its checks, or Windows starts and then freezes the moment you open File Explorer or Disk Management. Unplug one particular hard drive or SSD and everything is suddenly back to normal. That pattern is one of the clearest signs that the drive itself is failing, and how you handle the next few hours makes a real difference to how much data can be saved.
Why one bad drive can stall the whole computer
When a computer starts, the BIOS or UEFI firmware asks every connected drive to identify itself. Windows then does the same thing again as it loads, and again when Explorer or Disk Management lists your disks. A healthy drive answers in a fraction of a second.
A failing drive often cannot. If its read/write heads are weak, its firmware cannot load its own internal records, or the surface is full of unreadable areas, the drive can sit in a “busy” state while it retries over and over internally. The computer waits for an answer that never comes, so the logo screen hangs, the boot takes ten minutes, or Disk Management gets stuck on “Connecting to Virtual Disk Service”. A failing SSD whose controller is struggling can cause exactly the same stall.
The important point is that the computer is not the problem. It is waiting politely for a drive that is in trouble, and every one of those waits means the drive is working hard on damaged parts.
Common symptoms
- The PC hangs at the maker’s logo or the BIOS screen, but starts normally with the drive disconnected.
- Windows takes far longer than usual to reach the desktop.
- File Explorer shows “Not responding” when you click the drive, or the drive letter appears and vanishes.
- Disk Management or Diskpart freezes, or shows the disk with no size.
- An external USB drive makes the whole computer stutter as soon as it is plugged in.
- The drive clicks, ticks, whirs up and down, or is silent when it should be spinning.
The one test worth doing: unplug it
If you are not sure which device is to blame, power the computer off, disconnect the suspect drive (or unplug the external drive), and start it again. If the computer now starts normally, you have your answer. Do not plug the drive back in “just to check”. Every start-up attempt makes the drive try to read its damaged areas again.
If the drive in question is the computer’s only system drive, you cannot run this test easily. In that case, a computer that hangs before Windows loads, combined with any unusual noise or a recent drop or power cut, is reason enough to stop trying to boot it.
What not to do
- Do not keep restarting. Repeated power cycles are the most common way a recoverable drive becomes much harder to recover. Weak heads can fail completely, and on a drive with surface damage they can cause more.
- Do not let Windows run a disk check at start-up. If you see “Scanning and repairing drive”, that is CHKDSK working on a failing drive. It writes changes to the file system while the drive struggles to read it. Switch off and disconnect the drive. Our guide to bad sectors and why repair tools are risky explains this in more detail.
- Do not initialise or format it if Windows offers to do so. That message appears because Windows cannot read the drive properly, not because the drive is empty.
- Do not run free recovery software on it. Scanning a drive that hangs the computer means hours of reading from damaged hardware. Recovery software is designed for deleted files on a healthy drive, not for failing drives.
- Do not open it, tap it or put it in the freezer. Hard drives have to be opened in clean-room conditions, and old tricks like the freezer cause condensation on the platters.
Is it ever just a cable or a setting?
Sometimes. A faulty SATA cable, a loose connection or an underpowered USB port can cause slow detection too. On a desktop, it is reasonable to try one different SATA cable and port once. For an external drive, try the original cable in a USB port directly on the computer rather than a hub. If the computer still hangs with the drive connected, stop there. Swapping cables again and again does not help a drive that is failing internally.
If the drive also makes clicking, beeping or buzzing noises, or it was dropped or knocked, skip the cable test altogether. Those are mechanical symptoms.
What a recovery lab does differently
A lab does not connect the drive to an ordinary computer and hope. The drive is first examined to find out why it is not responding: heads, firmware, electronics or surface damage. If the heads are faulty, they are replaced in a clean room with matching donor parts. If the problem is firmware, it is dealt with at that level. Then the drive is copied sector by sector using equipment that can control timeouts, skip over unreadable areas, and come back to them later, so the healthy parts of the disk are saved first. Your files are recovered from that copy, not from the original drive.
This is why stopping early matters. A drive with slightly weak heads can often be copied almost completely. The same drive after a week of failed boots may have scratched platters.
What to do now
- Switch the computer off and disconnect the drive.
- Write down what happened: noises, error messages, any drop, power cut or update just before the problem.
- Note which files matter most, so recovery can be focused on them.
- If the drive is encrypted with BitLocker, find your recovery key (often saved to your Microsoft account).
- Get advice before trying anything else on the drive.
You can read more about our hard drive data recovery service in London, including how failed drives are assessed in our clean room.
Talk to Data Doctor
If your computer hangs whenever a particular drive is connected, switch it off and call Data Doctor on 020 7394 2529 for a free initial consultation. You can also bring the drive to our lab at Unit 1 The Willows, 80 Willow Walk, London SE1 5SY.