How to Fix and Repair Unallocated External Hard Drive without Losing Data [3+ Ways]

Tracy King updated on Nov 05, 2020 to Storage Media Recovery | How-to Articles

Does your external hard drive suddenly become unallocated or shows up as unallocated in Windows 10/8/7 PC? Relax! EaseUS hard drive recovery software with effective methods are available here to assist you in fixing unallocated hard drive without losing data in Windows 10/8/7.

When your external hard drive becomes unallocated, relax! Follow solutions on this page to fix external hard drive unallocated errors without losing any data.

Part 1. Restore data from unallocated external hard drive
Part 2. Repair unallocated external hard drive
Tips to prevent external hard drive from becoming unallocated

How to access unallocated external hard drive data

"Hey there, do you know how to fix external hard drive with unallocated error? My 1TB WD external hard drive suddenly shows up as unallocated in Disk Management on my PC. I don't want to format it for that I've saved quite a lot of important files on it. 

I cannot access saved data on the unallocated external hard drive, either. Help me please."

So how does your external hard drive become unallocated? Here is a list of reasons that may cause external hard drive or storage devices unallocated:

  • File system and internal device error 
  • Improper operations
  • Virus attack
  • Outdated disk driver

If you are experiencing the same issue on an external hard drive, USB drive, SD card or memory card, etc., stop using the device. In the following, you'll learn how to restore data, repair the unallocated external hard drive and tips to avoid the unallocated issue.

Part 1. Restore data from unallocated external hard drive

As most users use an external hard drive to save valuable files and essential data. And when the external hard drive becomes unallocated, to restore data becomes the top priority. 

With the help of professional data recovery software such as EaseUS Data Recovery Wizard, you still have a chance to recover data from the drive. How? 

This software enables you to recover lost data from unallocated space on a hard drive or external hard drive with ease. Download EaseUS hard disk recovery software here and follow the guide below to restore data:

Activation is required when you tend to restore all found files. Also, remember to save the recovered data to another secure device. 

Step 1. Choose the external hard drive

Since you're going to recover data from the external hard drive, run EaseUS Data Recovery Wizard and under the External Devices tab, choose the exact drive where you lost data. Click Scan.

select external hard drive

Step 2. Scan for lost data

The software will start immediately to scan all over the selected drive for all lost data. During the scan, you could see more and more data showing up in the results.

scan external hard drive

Step 3. Preview and recover data

After the scan is over, check the scan results for the desired data. You can preview the file by double-clicking on it. Click Recover and choose another location to save the recovered data.

preview and recover data

Part 2. Repair unallocated external hard drive

It's easy to fix the external hard drive unallocated issue. All you need is to create a new partition on the external hard drive, set NTFS or FAT32 as its file system.

Here, you can try two free methods provided below for help. 

# 1. [Automated] Repair unallocated external hard drive with partition manager freeware 

By creating a new partition on the unallocated external hard drive with a compatible file system, users can store files on the device again.

Free partition manager software like EaseUS Partition Master Free supports to do so within 3 steps:

If you want to create a partition on an empty USB, SD card or external hard drive, connect it to your PC in advance.

Step 1: Launch EaseUS Partition Master

On the main window, right-click on the unallocated space of your external storage device and select "Create".

Create partition on unallocated space

Step 2: Adjust the new partition size, file system, label, etc.

Set the size, partition label, drive letter, file system (NTFS), etc. for the new partition and click "OK" to continue.

Set up new partition

Step 3: Confirm to create a new partition

Click on the "Execute Operation" button and confirm to create a new partition by clicking "Apply".

Confirm and keep all changes

After this, you can save the previously restored data back to the external hard drive and even save more files on it again.

# 2. [Manual] Create a new partition on external hard drive with Disk Management

Another free method that you can try is to create a partition on the unallocated device by using Disk Management. Be careful while following steps here to fix the unallocated external hard drive issue:

  • Step 1: Connect the unallocated external hard drive to PC, enter Disk Management.
  • Right-click on This PC/My Computer > Manage > Disk Management.
  • Step 2: Locate and right-click on the unallocated space of the external hard drive, select "New Simple Volume".
  • Windows 10 disk management 2
  • Step 3: Set partition size, drive letter and file system (NTFS), etc.
  • Windows 10 disk management
  • Step 4: Click "Finish" to complete the process.
  • Windows 10 external hard drive partition

After this, you'll be able to use the external hard drive to save and store important data again. You can also transfer the previously restored data back into the external hard drive again.

Tips to prevent external hard drive from becoming unallocated 

Here are some practical tips that you can follow to prevent further unallocated errors from happening on your external hard drive and other storage devices: 

  1. 1. Update external hard drive driver.
  2. 2. Repair file system error on external hard drive with CHKDSK  or EaseUS partition manager software.
  3. 3. Run anti-virus software to clean up viruses in PC and external hard drive.
  4. 4. Use storage devices and unplug carefully from your PC.

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Frequently Asked Questions

1. Why choose EaseUS Data Recovery Wizard?

"EaseUS Data Recovery Wizard is the best we've seen. It's far from perfect, partly because today's advanced disk technology makes data-recovery more difficult than it was with the simpler technology of the past, but it's fast and efficient..."PCMag

"The first thing you'll notice about EaseUS Data Recovery Wizard Pro is that its interface is very clear and uncluttered, with only a small collection of self-explanatory controls. You won't find lots of extra options hidden in a system of hidden menus, either; what you see really is what you get."techradar

"Recover lost files, even after deleting a partition or formatting your drive."Macworld

2. Why cannot I recover 2GB data for free?

It is recommended to check the version installed is Free or Trial because they are different versions.

Trial has data preview function but cannot save any files, while the Free version enables to recover 2 GB files. The default free space is 500 MB and you may share the product on social media to get another 1.5 GB.

3. Why cannot the recovered files be opened?

A file is saved as 2 parts on the storage device: directory info (which is comprised by file name, time stamp and size info, etc.) and data content.

If the files with original file names and folder structures cannot be opened, one possible reason is the corrupted directory info. There is still a chance to recover the data content with the RAW Recovery method in our software.

4. Why isn't it suggested to recover the files back to the original drive?

The storage structure of the lost files would be altered or damaged by any changes on the drive. If you save the recovered files back to the same drive, the original data structures and data content would be corrupted or overwritten, which causes permanent data loss. So you should prepare another disk to save the files.

5. How can I check whether my data is recoverable or not before purchase?

The Free version helps you save 2GB files, so verify the recovery quality of our product before purchase.

6. How long does it take to scan the drive?

It strongly depends on the capacity of your hard drive and the performance of your computer. As reference,most drive recoveries can be completed in around 10 to 12 hours for a 1-TB healthy hard drive in general conditions.

About Data Recovery Wizard

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