Knowledge Center

Data Recovery After Drive Failure:

What to Do (and What Not to Do)

When a customer brings me a failed or inaccessible drive, the first step is determining whether the computer can detect and read it in Windows Disk Management. That determines whether normal data recovery is possible or whether the drive may require specialized clean-room recovery.

If the Drive Is Not Detected

If the drive is not detected and readable in Disk Management, I cannot scan it, copy files from it or access its partitions through normal recovery software. Windows must have usable access to the device before any software-based recovery can begin.

At that point, the drive may need to be sent to a specialized clean-room recovery facility. These facilities use equipment and procedures designed to recover data from drives with internal mechanical, electronic or controller failures.

Repeatedly reconnecting, restarting or attempting to operate a physically failed drive can make the damage worse. If the missing data is important, the safest choice is to stop using the drive and determine whether professional clean-room recovery is justified.

If the Drive Is Detected and Readable

If the drive is detected and readable in Disk Management, my first priority is copying the customer’s accessible data to a healthy drive.

I copy the data before running intensive tests, attempting repairs or changing the partition structure. A failing drive may stop responding at any time, so protecting the customer’s files comes before determining exactly what went wrong.

Test the Drive After Securing the Data

Once the accessible data has been safely copied, I test the drive for physical errors and examine the condition of its partitions.

If testing finds physical errors, the drive must be replaced. I will not return a failing drive to service simply because the files were successfully copied. Once a drive begins reporting hardware errors, it can no longer be trusted to store the customer’s data.

Physical Failure and Windows Corruption Are Different

A physically failing drive and a corrupted Windows partition are not the same problem.

A drive that reports physical errors is defective hardware and must be replaced.

A drive may also pass its physical testing while containing a corrupted Windows partition. That is a software problem rather than proof that the drive itself has failed.

A damaged Windows partition cannot be trusted or properly corrected by patching the existing installation. After the customer’s data has been backed up, I delete and recreate the partition and perform a fresh Windows installation.

Do Not Install Recovery Software on the Affected Drive

Recovery programs should never be installed on the same drive containing the missing data. Installing software writes new information to the drive and could overwrite files that might otherwise be recoverable.

Recovered data must always be copied to a separate, healthy storage device.

Data First, Diagnosis Second

The correct recovery process depends on what the computer can access:

• If the drive is not detected and readable in Disk Management, normal software recovery cannot proceed and specialized recovery may be necessary.
• If the drive is readable, copy the customer’s data before performing diagnostic tests.
• If the drive reports physical errors, replace it.
• If the hardware passes testing but the Windows partition is corrupted, recreate the partition and install Windows fresh.

The goal is to protect the customer’s data first, then determine whether the drive can be trusted or must be replaced.

Author: Richard Mallory, Home Net Computers

30+ Years of Professional IT Experience

Home Net Computers provides drive testing, data transfer and recovery evaluation throughout the Greater Seattle Area. Every drive is personally evaluated before recovery or replacement recommendations are made. 

Call 206-478-5001 or use our contact form to schedule service.