Corrupt HDD – 5 errors that destroy data
What not to do after HDD clicks, RAW prompts, CHKDSK errors or failed copies, and how to preserve the evidence before lab diagnosis.
See what you don't do →Dysk i Spółka • Data Recovery Laboratory
Data Recovery Lab Blog - Guides and Case Studies
This is the laboratory's organized knowledge base: guides, failure scenarios and case studies. If you already know you need help, choose the most relevant route below.
This archive collects only blog content: guides, checklists and case studies. Service, local and sales pages are excluded from the feed so that the blog remains readable and truly useful. Once you recognize the symptom, go to the appropriate service page:
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Start with the right topic cluster
If you're coming here for the first time, go to the section that best suits your storage device or environment. This makes it easier to separate educational guides from service pages and choose the right next step.
- HDD - failure symptoms, RAW, CRC and mechanics
- SSD/NVMe - TRIM, brick and no detection
- RAID/NAS - "degraded" and "offline" statuses and company failures
- Flash and memory cards - SD, CFexpress, USB flash drive
- Monitoring / DVR / NVR - recordings, retention and recovery after deletion
- Companies / GDPR - accounting, RAID/NAS incidents and business continuity
- Case studies - real scenarios from the laboratory
Forget about backup. Configure it once and it will take care of itself - on Windows and Mac.
Backup is supposed to work on its own, but only once someone gets the scheduling, versioning, and recovery testing right. Here's a specific plan for Windows and macOS.
See copy plan →
Read: RAID failure in a company — what to do without making it worse
In the RAID array, panic causes the most damage: restarting, rebuilding or replacing the disk on a whim. Check how to secure the situation before you lose further data.
See first decisions →
CRC error while copying files: what it really means
Learn when a CRC error is a cable issue, when sectors are failing and when another copy attempt may make the recovery harder.
See safe steps →
Unknown, uninitialized disk: should you initialize it?
Initialization can overwrite metadata. Check what the Windows prompt means before you click OK on a disk that still contains needed files.
Check before initialization... →
Read: SSD and NVMe bricking — what it means and why it most often happens during data recovery
What SSD/NVMe bricking means, why it can happen during recovery attempts and why power cycling is risky.
Check Brick's symptoms →
What a professional laboratory does that you can't do at home
Not everything can be recovered with a scanner, software and patience. This text shows where home methods end and real laboratory work begins.
See when you'd stop trying →
Read: RAID failure in a company — what to do without making it worse
A plan for the first 24 hours after a NAS or server failure: how to stop the damage, what to document, and when to discontinue independent operations.
See the plan for the first 24 hours →
What not to do if the data matters
This is a short list of actions that most often kill the chance of recovery: from formatting to random "repairs" from the Internet. Better read it before clicking for the first time.
See what you don't do →
SSD vs HDD – which drive is safer?
A practical comparison of reliability, failure modes and what each drive type means for your data.
Compared to the risks of HDD and SSD →
Drive will not boot: black screen and data risk
A black screen after connecting the drive does not always mean a damaged system. We describe how to distinguish a storage-device problem from a computer fault and what not to do blindly.
Check the first steps ’
RAW disk – why not click
The RAW status looks scary, but the biggest mistake is to quickly click "Format". In this guide, we explain what RAW means and how to stop the problem from escalating.
Do not confirm formatting →
RAW drive after a power outage: what happened?
Power loss can interrupt file-system writes and expose weak sectors. See what to check before running repair tools.
Check for signs of power failure →
RAW drive after connecting it to another computer
After being connected to another computer, the storage device may suddenly go RAW due to the power supply, file system or a previously hidden fault. We check the most typical scenarios.
Safe first step →
External USB drive shown as RAW: safe first steps
Separate cable, bridge, power and file-system symptoms before formatting the device or running automatic repair.
See safe steps →
Disk rattles when you start your computer - what does it mean and when should you stop trying immediately?
Clicking can point to head, spindle or service-area trouble. Stop repeated power cycles and write down the sound pattern.
Check what not to run →
RAW drive asks to be formatted: what it means
The formatting message often appears exactly when the data is still salvageable. The most important thing is one thing: do not confirm anything without a diagnosis.
Do not confirm formatting →
Strange HDD noises: clicking, scraping and grinding
Clicking, knocking and squeaking are not "operational characteristics", but symptoms of a mechanical failure of the HDD. We've collected the most common sounds and what each of them may mean.
Check for HDD crash symptoms →
"The drive needs to be formatted" - what to do
A format prompt does not mean the files are gone. Check what to do before confirming anything.
Do not confirm formatting →
When you lose data - the worst possible time to experiment
Data loss is a bad time to test random advice from the web. This text organizes what to do right away and what is better not to touch at all.
Check the first steps after data loss →
How much does data recovery cost? specific price ranges and what the quote depends on
The price of recovery depends on the type of storage device, the type of damage and the scale of laboratory work. We break down the topic into specific ranges and factors that really influence the quote.
See what the price depends on ’
How to safely store photos, projects and documents - a simple backup plan for a small business and a photographer
A simple backup should be realistic for implementation, not just nice to present. We show copy layout for small business, photographer and people working on important projects.
See copy plan →
How to recover data from a damaged HDD safely
Recovery from HDD starts with recognizing the symptoms, not with installing another program. Here we separate logical, electronic and mechanical failures into specific scenarios.
Check the first steps ’
🔍 How to recover deleted recordings from NVR/DVR? step-by-step guide and problem diagnosis
Deleted recordings from the DVR are not always lost immediately, but time is against you. We explain what the recovery chances in DVR and NVR depend on.
See how to secure the recordings →
Read: SSD vs HDD: which drive is really more reliable, and what does it mean for your data?
Minutes count on SSD, because TRIM and garbage collection can quickly change the situation after deleting files. We explain when recovery is still realistic.
See how TRIM works →
Case study: a flooded wedding photographer's laptop
A real case with wedding material that seemed to be lost after the equipment was flooded. We show the course of diagnosis, risks and the final result of recovery.
See script analysis →
HDD, SSD, or cloud? How to choose the perfect storage device to backup your data
Not every backup needs NAS and the corporate cloud. We compare HDD, SSD and online services in terms of cost, convenience and data security.
Check the score →
What is a working day like in a data recovery lab?
What does a working day in the laboratory look like? Without marketing fog: diagnosis, securing storage devices, sector copies and decisions that need to be made before the actual recovery begins.
See the lab's work →
How to protect material from a single job: backup workflow for a photographer and videographer
One order without a backup may result in the loss of all material and reputation. This workflow organizes backup for the photographer and cameraman immediately after the photos.
See copy process →
How to secure surveillance recordings - backup and GDPR
Monitoring must be secured so that the recordings are valuable when they are really needed. We discuss copies, retention and the basics of GDPR compliance.
See how to secure the recordings →
JFS vs. XFS – why the DVR/NVR file system matters
In recorders, the file system is sometimes more important than the device model itself. We explain why JFS and XFS are so important when recovering recordings.
Verify DVR/NVR filesystem →
Read: Memory card or USB flash drive not working? Stay calm — your data may still be recoverable.
The card or USB flash drive may stop responding without any prior warning. We show the first steps that help, instead of hammering out the USB flash drive.
Check for signs and symptoms of storage device →
When to stay still and when to act? first aid after a laptop has been flooded or a hard drive has fallen.
After flooding, the pace is important, but the correct sequence of actions is even more important. Here's a simple checklist: what to disconnect, what not to dry and when to stop starting attempts.
See first steps →
Computer does not see the external drive
A glowing LED and silence in the system is a common scenario with USB drives. We show you how to distinguish the problem of the housing, cable, power supply and the storage device itself.
Check for USB symptoms →
Do not format before data recovery guide thumbnail
This is one of the most expensive myths in data recovery. The "trial" format can retrieve files that could have been saved a moment earlier.
Prove why not format →
Do not install recovery software on the source drive
Recovery software saved on the same drive may overwrite the exact files you are looking for. We explain why this mistake is so common.
The risk of overwriting →
Do not open a hard drive at home
An open HDD outside the cleanroom quickly collects dust and loses the chance for safe recovery. We'll show you why "I'll just see for a moment" is a very bad idea.
See what you don't do →
Do not use CHKDSK/"repair filesystem" if the disk is damaged
CHKDSK can clean up the file structure at the expense of some data. In the article we explain when such a repair does more harm than good.
Check CHKDSK's risk →
Need help? Start with a safe laboratory assessment of the storage device
A short guide for people who prefer not to experiment on their own. We explain what a storage device notification looks like and what happens next after contacting the laboratory.
See how to describe symptoms →
RAID 5 shows "degraded" but the drives look healthy — what should you do?
Why RAID 5 can report degraded even when every drive appears healthy, and what to check first.
See the first decisions before rebuilding... RAID →
RAID is not a backup - how companies lose data in 5 minutes
Why redundancy is not the same as a verified backup, especially during rebuilds and operator mistakes.
Check the emergency plan →
QNAP NAS ransomware: how to recover without paying the ransom
A case study of the QNAP attack: what we secured, what was recoverable, and why paying a ransom wasn't the only option.
Read the article →
GDPR at home: How to protect private data from leakage?
Private data is also worth protecting like company data: copies, encryption, order on devices and less risky habits. Here's a simple plan without the legal jargon.
Read the article →
Damaged HDD drive – what to do, what absolutely not to do?
If the HDD has died, the first decisions are the most important: do not reboot, do not format and do not open the case. This guide breaks it down step by step.
Read the article →
First 24 hours after a company server or NAS failure
Datastore crash after reboot case study: what secure LUN analysis and recovery looks like in an enterprise environment.
Read the article →
WD My Passport I/O Device Error diagnosis
I/O Device Error in WD Passport often starts with slowdowns, disconnections, or copy errors. We explain how to distinguish a USB problem from a real storage device failure.
Read the article →
Secure what you can – but wisely
When you're stressed, it's easy to copy everything at once and replace the damaged media. This text tells you what to protect first and how to do it sensibly.
Read the article →
External drive disconnects while copying
Disconnecting while copying usually indicates instability that will get worse. We show when the hardware is to blame and when the disk itself fails.
Read the article →
RAID degraded/offline: what not to do before a lab
The most common errors with arrays in the "degraded"/"offline" status are blind rebuilds and repairs in production. We show a safe procedure.
Read the article →
SSD not detected in BIOS: what to do safely
Steps to avoid when an SSD disappears from BIOS, Windows Disk Management or a laptop boot menu.
Read the article →
TRIM and deleted files on SSD recovery chances
Deleted files on SSD are always a race with TRIM. We explain what the chances of recovery depend on and when it is worth acting immediately.
Read the article →Initial lab assessment • NDA/GDPR • Secure imaging
Do you have a specific symptom? Describe the case in the form
The blog and case studies help to sort out the problem, but we only diagnose the case after analyzing the symptoms. Describe the failure in the form or call: 573 532 490.
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