If you have multiple partitions on your hard drive, nothing will scare you more than booting up your computer and finding that one partition has seemingly disappeared. What used to be a partition full of files, is now unallocated space that can’t be accessed.

This can happen for a multitude of reasons, reasons that we’ll take a closer look at in this article. While it may be easy to start freaking out, you must know that there are options available for recovering both the files on the partition, and in some cases, the entire partition itself.

How to Recover an Unallocated Partition

What Is an Unallocated Partition?

Partitions are segments of a hard drive that have been logically separated to organize the data stored on it. A single drive can have multiple partitions. When you look at your drive and see unallocated space, this references space on the hard drive that hasn’t yet been allocated to a partition.

Unallocated space cannot store files or programs, and is basically useless to the operating system unless the space is used to create a new partition or is added to an existing partition to extend it.

Reasons Behind Unallocated Partitions

A brand new hard drive will come without any partitions. When you install it, you will need to create at least one partition as part of the operating system installation process. Any space that isn’t dedicated to a partition will remain as unallocated space.

However, unallocated space can appear as a result of something else. Here are a few common reasons why there may be unallocated space on your hard drive:

  • Lost or deleted partition – If a partition has been deleted, corrupted, or lost for one reason or another, the partition will be converted to unallocated space, also known as an unallocated partition.
  • 🦠 Malware of virus attack – Viruses can be designed to specifically target the partitions of your hard drive. If a virus has deleted your partition, the partition that was once there may appear as unallocated data.
  • Hardware failure – Hard drives are susceptible to failure. If the hard drive has failed at some point, the partition could have become lost as a result.
  • 🔌 Unexpected power failure – If your computer lost power during a write process to the drive, it could cause some data to become corrupted and the partition deleted.

How to Recover Data from an Unallocated Space

No matter what causes your partition to disappear, there are various methods you can use to recover the data that was lost.

Restore from a backup

If you’ve created a backup of the volume that was lost, you can use this backup to easily restore the files that were lost. Restoring from backups is probably the most effective way of getting back all the files that were lost with the most success.

Restore from a backup

If you don’t have a backup, then you will need to move onto the next solution to recover your files.

Using recovery software

Your next best option for recovering data from a recently unallocated partition is through the use of data recovery software. There are numerous data recovery solutions on the internet, and for this solution, we’re going to be using Disk Drill.

  1. Download and install Disk Drill. Open it.
  2. On the opening screen, select the unallocated space that used to be your partition. Click Search for lost data. Recover an Unallocated Partition with Disk Drill
  3. When the scan has finished, click on Review found items. Review found items
  4. Select the files you want to recover by checking their checkbox. Click Recover. how to recover unallocated partition
  5. Choose a location to recover the files to. Click OK. recover the files
  6. When file recovery is complete, you can view your recovered files by clicking Show recovered data in Explorer. Show recovered data in Explorer

Using a recovery service

If none of the previous methods worked for you, or if you’re not particularly confident performing the steps necessary, then you might be better off using a professional recovery service.

Recovery companies employ the services data recovery specialists that you can send your faulty drive to. Their job is to recover your data using commercial-grade tools and solutions to give you peace of mind.

cleverfiles data recovery service

While this method may take the longest since you need to send your drive away, it will have the highest success rate as you’re leaving the recovery part to the professionals.

How to Fix an Unallocated Hard Drive

If your partition has disappeared from your drive, you can create a new one after successfully recovering the data that was on the last one.

Delete the old volume using DiskPart

CMD, the command-line tool native to Windows, can work wonders in repairing a hard drive that recently lost a partition. Sometimes the volume may need to be manually deleted. Using the diskpart command, you can delete the old partition so that you can create a new one.

  1. Right-click on your Start button and select Run. Type diskpart and press Enter. If Windows asks you to give permission, click Yes.
  2. In the new Diskpart window that opened, type list volume and press Enter. Delete the old volume using DiskPart
  3. Type select volume <number>. For the number, enter the volume number that was lost. Press Enter. select volume <number>
  4. Type delete volume and press Enter. This will erase the volume. delete volume and press Enter

When you’ve finished deleting the old volume, you can move onto creating a new volume to replace it with the next set of steps.

Create a new partition with Disk Management

Disk Management allows you to manage the hard drives in your computer, as well as external drives. We’ll be using Disk Management to create a new partition to replace the one that was lost.

  1. Right-click the Start Button and click Disk Management. Create a new partition with Disk Management
  2. Right-click the unallocated volume. Click New Simple Volume. New Simple Volume
  3. When the New Simple Volume Wizard opens, click Next
  4. Specify a size for the new partition. Click Next. Click Next
  5. Choose a drive letter, then click Next. Disk Management - Step 4
  6. Specify a volume label, and leave everything else as default. Click Next. Disk Management - Step 5
  7. On the final screen, click Finish.

After the final step, the new volume will appear in Disk Management. You can also access it in Windows Explorer and begin moving files to it.

Update your drivers

To ensure your hardware components are performing at their best, you need to keep them updated with the latest firmware. If the drivers for your hard drive are outdated, this can cause partitions to become lost. If you update your drivers, your partition may become visible and usable again.

  1. Right-click the Start button and click Disk Management. Update your drivers
  2. At the bottom of the window, right-click the unallocated volume. Click Properties. Click Properties
  3. Click on the Driver tab, then Update Driver. Update Driver
  4. Click Search automatically for drivers. Windows will then search for the most up-to-date drivers associated with your hard drive and install them. Search automatically for drivers
  5. Restart your computer.

If this hasn’t worked for you, try going back to the same window from Step 3 and clicking Uninstall Device then Uninstall. Restart your computer, and Windows will download the drivers again.

Tips to Maximize the Success Rate of Unallocated Recovery Partition

Data recovery can be made a lot easier with a few simple steps. Some of these steps can be performed immediately, while others are more for protecting your data in the long-run.

  • 🛑 Stop using the disk – Even though unallocated portions of the hard drive aren’t used to store files by the operating system, it’s a good idea to stop writing anything to the disk at the risk of overwriting any data that needs to be recovered.
  • 🙅‍♀️ Don’t create a new partition – If you create a new partition over the partition that was lost, you run the risk of losing the data that was already saved to the disk. Because of this, you shouldn’t create a new partition until you’ve recovered the files from the partition that was lost.
  • Don’t extend existing partitions – Much like creating a new partition, extending an existing partition can lead to the existing data being overwritten. Until you’ve recovered the lost or deleted data, don’t extend any of your existing partitions.
  • 🗂️ Backup existing files – Backing up is the key to a successful recovery. If you take the time to regularly backup your files, you can bounce back almost immediately in the event of catastrophic data loss. If you have a handful of files, consider using cloud-based solutions like Google Drive or Dropbox. If you have a lot of large files, get an external hard drive that you can copy your files to. In the event that you’ve lost your partition, consider backing up your accessible important files immediately.


Even though losing a partition can be a scary moment, you can put your mind at ease by following the solutions outlined in this article. If done correctly, you can recover your files without much effort. Data recovery from a recently unallocated partition heavily depends on how long ago the partition was deleted and whether or not any new data was written to the drive.


Jordan Jamieson-Mane

Jordan Jamieson-Mane is a technology content writer with a passionate interest in technology. Starting from a young age, this interest gradually turned into a career, with Jordan studying in the field of IT and moving int...

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Approved by
Brett Johnson

This article has been approved by Brett Johnson, Data Recovery Engineer at ACE Data Recovery. Brett has a Bachelor's Degree in Computer Systems and Network, 12 years of experience.