The First Rule: Stop Using the Drive
The most important thing to do when you suspect a hard drive is failing is to stop using it immediately.
This sounds counterintuitive — your instinct is to keep trying, to restart the computer, to copy files off. But every additional read or write operation on a failing drive can overwrite recoverable data or extend physical damage to areas of the drive that were previously intact.
Power down the computer as soon as you suspect a drive failure. Do not restart it to “try again”. Do not attempt to run the computer from the failing drive while you decide what to do.
How to Recognise Hard Drive Failure
Not all drive failures are obvious. Some come with clear warning signs; others fail suddenly with no advance notice.
Gradual failure signs:
- The computer has become progressively slower over weeks or months
- Files occasionally fail to open or take much longer than usual
- The computer freezes and requires a hard restart
- You hear clicking, grinding, or scraping sounds from the drive (mechanical HDDs only — SSDs are silent)
- Windows or macOS shows disk errors or asks to run a check
Sudden failure:
- The computer won’t boot — instead showing error messages like “No bootable device”, “Operating system not found”, or a flashing folder with a question mark (Mac)
- The drive is not recognised at all by the operating system
- Blue screen errors (Windows) with disk-related error codes (CRITICAL_PROCESS_DIED, UNMOUNTABLE_BOOT_VOLUME, etc.)
If your computer has been making clicking or grinding noises for days and you’ve ignored it, the drive has been telling you it’s failing. The noise from a mechanical hard drive is almost always a precursor to complete failure.
What NOT to Do
Don’t run CHKDSK or Disk Utility on a failing drive
Windows’ CHKDSK and macOS’s First Aid (Disk Utility) are repair tools. They attempt to fix filesystem errors by rewriting data on the drive. On a healthy drive, this is fine. On a physically failing drive, this can destroy recoverable data by overwriting it during the repair attempt.
If you’re running these tools because your computer is slow or having issues, that’s reasonable. If you’re running them because you suspect the drive is physically failing — unusual noises, the drive not being recognised, the computer not booting — don’t.
Don’t install data recovery software onto the failing drive
Data recovery software works by reading the drive and reconstructing file structures. Installing the software to the same failing drive you’re trying to recover data from adds writes to the drive and potentially overwrites the very data you’re trying to recover.
If you want to attempt a software recovery, install the recovery software to a separate drive (a USB stick or a second hard drive), then run it pointed at the failing drive.
Don’t freeze the hard drive
There’s an old folk remedy for failing hard drives that involves putting them in a freezer. This does not work reliably, can introduce condensation that causes additional damage, and is not recommended. Ignore this advice.
Don’t open the drive casing yourself
Hard drive platters are machined to tolerances tighter than a fraction of a human hair. The read heads fly nanometres above the platter surface. Opening a hard drive outside of a cleanroom introduces particles that cause the heads to crash into the platters, typically destroying any remaining chance of recovery. Do not open a hard drive yourself.
What TO Do
1. Power down immediately
As above — the moment you suspect failure, shut down the computer. If Windows or macOS won’t shut down normally, hold the power button until the machine powers off.
2. Identify what data you need
Before contacting anyone, think about what’s actually on the drive. It’s easy to panic about “everything” — but in practice, the files that matter most are often a specific subset: the work folder, the photos folder, emails.
Knowing what you need helps a recovery workshop prioritise and helps you assess whether the cost of professional recovery is proportionate to what’s at stake.
3. Check for recent backups
This is the time to find out whether your backup actually worked. Check:
- Time Machine (Mac): Is there a recent backup on an external drive or Time Capsule?
- Windows Backup / File History: Was this set up? When did it last run?
- Cloud storage (OneDrive, Google Drive, iCloud, Dropbox): Which folders were syncing? How recently?
If a full backup from last night exists, you don’t have a data loss problem — you have a hardware replacement problem, which is much simpler. If the last backup was from 18 months ago, the stakes are higher.
4. Do not attempt DIY recovery on a mechanically failing drive
Software data recovery tools (Recuva, TestDisk, R-Studio, PhotoRec) work well for accidentally deleted files or logically corrupted drives where the hardware is still functioning normally. They do not help with mechanically failing drives — a drive that’s making clicking noises, isn’t spinning up, or isn’t being recognised by the computer.
For mechanically failing drives, professional data recovery in a controlled environment is the appropriate path.
5. Contact a recovery specialist promptly
Time matters with some drive failure modes. A drive that’s in a partial failure state can progress to complete failure if left powered off for extended periods in certain conditions, or if it continues to be accessed.
A professional data recovery assessment will determine:
- Whether the drive failure is logical (filesystem or software issue) or physical (mechanical or electronic hardware fault)
- What data is recoverable and at what estimated cost
- Whether the recovery needs to be done in-house or at a specialist clean-room facility
Logical vs Physical Failure: What’s the Difference?
Logical failure: The drive hardware is physically intact, but the filesystem has become corrupted, partitions have been accidentally deleted, or the operating system files have been overwritten. Recovery success rates for logical failures are high. Cost is generally lower.
Physical failure: The drive has a hardware fault — a failed read/write head, damaged platters, seized motor, or failed controller board. Recovery requires physical intervention. Success rates vary depending on the extent of damage. Cost is higher, and for severe cases, specialist clean-room facilities are required.
Most of the drives we assess fall into one of these categories, and initial triage takes only a short time. We’ll give you a clear indication of which type of failure you’re dealing with and what we expect to recover before you commit to any cost.
What a Professional Assessment Involves
At our Putney workshop, a data recovery assessment includes:
- Visual inspection of the drive and connector
- Non-destructive imaging attempt (where feasible) to assess the extent of readable sectors
- SMART data review for mechanical drives
- Preliminary identification of logical vs physical failure
We give you a written summary of what we found and what we can recover, with a clear quote before any recovery work begins. If recovery isn’t feasible, we’ll tell you that too — we won’t take money for work that isn’t going to succeed.
Call 020 7610 0500 or contact us as soon as possible. The sooner a failing drive is assessed by a professional, the better the odds of a successful recovery.