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“Access denied” on their own backup drive.

An accounting firm could see their Iomega external, and Windows would not let them open it. The question that decided the whole job was whether that was a permissions problem or an encryption one — because only one of those has an answer.

DeviceIomega external · WD inside
FaultCorrupt NTFS permissions (ACL)
Turnaround4 days
OutcomeFull recovery
ToolsWrite blocker · ACL rebuild

The situation

An accounting company kept client records, invoices and tax data on an Iomega external drive used as their working backup. One morning Windows began returning “Access is denied” when anyone tried to open it. The drive was detected, it appeared in Explorer, and it would not let anybody in. Their accounting software could not read from it either, and attempts to change permissions through the Windows security settings failed.

They stopped there rather than persisting, which was the right decision — forcing ownership changes on a drive whose file system may be damaged can make matters considerably worse.

First look and diagnosis

The first question with an access-denied drive is the one that decides everything: is this permissions, or is this encryption? They present almost identically to the user and they have completely different outcomes.

Here it was permissions. The NTFS access control lists — the records attached to each file and folder describing who may read them — had been damaged, along with some directory metadata. The drive was not encrypted, and the data itself was entirely intact and simply unreachable behind ownership records that no longer resolved to a valid account. Inside the Iomega enclosure was an ordinary Western Digital drive, mechanically healthy throughout.

Worth stating plainly, because it is the counterfactual that matters: had this been BitLocker or third-party encryption with no key available, the answer would have been no. Encryption cannot be undone by us or by anyone without the key, and we would have said so at the diagnostic rather than after a bill.

The recovery

The drive was imaged sector by sector behind a hardware write blocker before anything was attempted, so the original could not be altered by any subsequent step. Everything afterwards ran against that copy.

From the image, the surviving access control lists were read directly and the damaged ones reconstructed, with ownership reassigned to a valid account while the underlying file data was left untouched. Directory metadata that had become inconsistent was rebuilt from the file system's own redundant structures. At no point was the original drive written to.

Verifying and returning the data

Verification here meant more than opening files. The firm's accounting software was the actual test — a spreadsheet that opens in Excel but that Sage will not import is not a successful recovery for an accountant. Tax records, invoices and payroll data were confirmed readable by the software that needed them before anything was signed off.

Outcome

A complete recovery, returned on fresh media. Nothing had ever been physically wrong with the disk — the entire failure was a set of damaged permission records standing between the firm and their own data.

The wider point is worth keeping: an access-denied drive is frequently the cheapest problem on this site to solve, and occasionally the most expensive. Which one it is depends entirely on whether encryption is involved, and that is established for free before anyone commits to anything.

Access denied usually means permissions, not encryption

On a drive moved between machines, or from a computer that has been rebuilt, “access denied” is normally an ownership problem — and taking ownership through Windows security settings often fixes it in two minutes at no cost. Where it does not, the file system may be damaged and forcing it can make things worse. Where the drive is genuinely encrypted and the key is gone, no firm can open it. A single external drive is from £300 +VAT after a free 48-hour diagnostic.

// sending your device in

Two simple steps.

Get the device to us for a free diagnostic and a quick note on what went wrong — an engineer looks it over and puts your exact quote in writing before anything is started.

1

Send us your device

The route to your data starts with the device reaching us. Box it up securely, tuck your contact details inside, and send it across — after the free diagnostic, we put your exact price in writing before a single step is taken.

How to pack it
  • Box the device up in a small, sturdy carton or a padded envelope.
  • You can leave out caddies, cables and power supplies — none of them are needed for the recovery.
  • Pop your details inside — name, address, phone and email, on a slip of paper or via our shipping form — and seal it up.
Post toOxford Data Recovery
John Eccles House, Oxford Science Park
Oxford OX2
Shipping formPDF · print & include with your devicePDF ↓

Sending it by post? Go with a tracked, insured service. Prefer to bring it round? Our door is open Monday to Friday, 9am to 5:30pm — just pack the device as described above beforehand.

2

Need more information?

Prefer to get a sense of things first? Complete the form with a bit more about the fault and an engineer will look it over and send back a tailored quote.

Every enquiry is read by an engineer in person — daytime replies usually land within 30 minutes. Rather talk? 01865 593000.

Thanks — your message is in.

We’ll get back to you soon. Anything pressing, call 01865 593000.

Common questions

My external drive says “access is denied” — what does that mean?

Usually that the NTFS permissions no longer resolve to a valid account — common on a drive moved between machines or from a computer that has been rebuilt. It is a permissions problem rather than damage, and the data is generally untouched behind it.

Can I fix it myself?

Often, yes. Right-click the drive, Properties, Security, Advanced, change the owner and apply to subfolders. If that works you need nothing else. If it fails, the file system itself may be damaged — and repeatedly forcing ownership changes at that point can make matters worse.

What if the drive is encrypted rather than permission-locked?

Then the answer is different and it is worth knowing early. BitLocker, FileVault and third-party encryption cannot be opened without the key or password — by us or by anyone. Any firm claiming to reconstruct a missing decryption key is not describing something that is possible.

How do you tell the two apart?

The diagnostic establishes it, at no charge. Permission damage and encryption present almost identically to the user and have completely different outcomes, so it is the first thing we settle before quoting anything.

What does Iomega drive recovery cost?

From £300 plus VAT for a single external drive, quoted in writing after a free 48-hour diagnostic. Send the unit complete with its enclosure rather than removing the disk inside.

Related

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