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PC FIX
Storage

Issue with new disk showing as Unallocated

If the current symptom is closer to “disk unallocated”, first check whether the new disk has no partitions or whether the partition table may be damaged. Check the recognition location in BIOS and Disk Management and cross-test cables, ports, and slots.

Solving Order
We've organized the methods starting with the simplest and least expensive ones. Please check the solutions one by one, starting from the top.

Do you have these symptoms?

  • Disk unallocated
  • unallocated
  • No new SSD partition

main causes

  • New disk has no partitions
  • Possible partition table corruption

How to solve

Please check them in order from the top. If the issue is resolved, you do not need to proceed to the next step.

1

Recheck cables, ports, and slots

When it comes to failure to recognize a storage device, the quickest way to rule out a connection problem is to start with it.

Difficulty Moderate time 10-20 minutes cost 0 won
  1. 1External devices use different USB ports and cables.
  2. 2Turn off the SATA device and check that the data and power cables are installed.
  3. 3For M.2 devices, check your motherboard documentation for supported slots and sharing requirements.

confirmation point

After these steps, see if the “Disk Unallocated” symptom decreases or disappears. If there is no change, also check the possibility that there are no partitions on the new disk in the next step.

2

Check the location visible in BIOS and Disk Management

The cause varies depending on whether it is not visible in the BIOS or only in Windows.

Difficulty Moderate time 5-10 minutes cost 0 won
  1. 1Verify that the drive is visible in BIOS/UEFI.
  2. 2In Windows, open Disk Management and check if the disk is visible.
  3. 3If it's a new disk, check if you need a partition and drive letter.
3

Cross-test on another port or another PC

This will help you determine whether the problem is with your drive or your PC.

Difficulty Moderate time 10~30 minutes cost 0 won
  1. 1Connect the external drive to another PC.
  2. 2Compare internal drives using different slots and cables if possible.
  3. 3If it is not recognized in other environments, it is likely a problem with the drive itself.
4

Update or reinstall storage/chipset drivers

Outdated or corrupted storage/chipset drivers can cause the symptom.

Difficulty Moderate time 10~30 minutes cost 0 won
  1. 1Check the device in Device Manager.
  2. 2Check your PC or component manufacturer's site for storage/chipset drivers for your current model.
  3. 3If the problem started immediately after an update, consider rolling back to the previous stable version.
  4. 4After installing the driver, restart your PC.
5

If you have existing data, do not initialize or format it.

If you reset or format while troubleshooting recognition issues, your existing data may be at risk.

Difficulty Moderate time immediately cost 0 won
  1. 1If the disk has existing data, do not click ‘Initialize’ or ‘Format’ right away.
  2. 2If you have data that needs to be recovered, minimize write operations.
  3. 3If your data is important, consider professional recovery.

Precautions

If you need the existing data on the drive, do not initialize or format it before checking the cause.

Frequently Asked Questions

We've put together a list of things we frequently check regarding this issue.

Related issues

If the symptoms do not match exactly, please check the issue below.

Storage

SSD appears in BIOS but not in Windows

If “SSD not recognized by Windows” repeats, it is better to narrow it down to no partition/drive letter and storage driver rather than changing several settings at once. Check the recognition location in BIOS and Disk Management and cross-test cables, ports, and slots.

View solutions →
Storage

SSD or NVMe not recognized in BIOS

Among storage device problems, the “SSD BIOS not recognized” symptom may be related to poor mounting or slot/shared lane restrictions. Check the recognition location in BIOS and Disk Management and cross-test cables, ports, and slots.

View solutions →
Storage

Hard disk not recognized problem

When troubleshooting a hard disk not being recognized problem, it is important to rule out the causes one at a time. Based on the “HDD not recognized” symptom, check for SATA data/power cable problems, port or drive failure, and then proceed to the next step. Check the recognition location in BIOS and Disk Management and cross-test cables, ports, and slots.

View solutions →
Storage

Problem with external hard drive or external SSD not being recognized

If “external hard drive not recognized” repeats, it is better to narrow it down to USB cable/port issues or power shortage rather than changing multiple settings at once. Check the recognition location in BIOS and Disk Management and cross-test cables, ports, and slots.

View solutions →

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