Fix and Repair Unallocated External Hard Drive without Losing Data

Did your external hard drive, USB drive or SD card etc suddenly become unallocated? Relax! Here you'll find solutions to fix unallocated errors on your hard drive/external hard drive, USB or SD etc storage devices without losing any data now.

Note: If you need a quick solution to fix and repair your unallocated external hard drive or internal hard drive in your PC, you can just jump to Part 3 and get your problem solved now. 

Part 1. How to access unallocated external hard drive data? 

"Hey there, do you know how to fix external hard drive with unallocated error? My WD 1TB 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. How can I get my data back? Help me please."

Are you having the same issue with your external storage device, such as external hard drive, USB drive, SD card or memory card etc that suddenly shows up as unallocated in PC? How to fix the problem when you cannot access the saved data? And why does it become unallocated? Here, in the following instructions, you'll find answers and solutions. 

Part 2. What makes an external hard drive become unallocated?

So how does your external hard drive become unallocated? If you know the exact reasons that might cause this issue, you'll be able to find ways to avoid these issues so as to prevent un-allocation issues from happening to external hard drives. 

Here below you'll find a list of reasons that may cause external hard drive or storage devices unallocated:

• File system error.
• External hard drive internal error;
• Improper operation such as unplugging drive improperly from PC.
• Virus attack.
• Hard drive driver is outdated etc.

How to avoid these issues? Here are our suggestions: 

1. Update hard drive driver; 
2. Run CHKDSK to fix internal error on external hard drive;
3. Run anti-virus software to clean up viruses in PC and external hard drive;
4. Use storage devices and unplug carefully from your PC.

Part 3. How to repair and fix unallocated external hard drive without losing data?

# 1. Restore data from the unallocated external hard drive

Though your external hard drive shows up as unallocated in your PC, you can still have a chance to recover data from the drive. How? Professional data recovery software - EaseUS Data Recovery Wizard Free can help.

This software allows you to recover lost data from unallocated space on partition hard drive with ease. All you need is to free download it, activate it and follow the guide below  to restore data from your unallocated external hard drive now:

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.

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.

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.

# 2. Fix and repair unallocated external hard drive into reusable again
Format and recreate a new partition

After restoring data from the unallocated external hard drive, you can now repair it. How? Follow the given methods below for help now:

Method 1. Use CMD and disk management to fix "external hard drive unallocated" error

• Open Diskpart and type: list volume and hit Enter.
• Type: select volume X and hit Enter. (X is the drive letter of your unallocated external hard drive.) 
• Type: delete volume and hit Enter.
• Type: list volume and hit Enter. (If the Disk Management tool cannot create a new volume on it, continue the steps below.)
• Type: select volume X and hit Enter.
• Type: delete volume and hit Enter.
• Type: delete volume override and hit Enter.
• Enter Disk Management and right-click the unallocated external hard drive to create a new volume and set the file system to get fix the unallocated error on an external hard drive.

By doing this, you'll be able to use the external hard drive to save and store important data again.

Method 2. Use partition manager freeware to fix and repair the unallocated external hard drive

If you are not quite familiar with computer administrating jobs, don't worry. You can apply a free partition manager software - EaseUS Partition Master Free with its Check File System and Create Partition features to fix the unallocated issue with ease.

1. Preparation: Connect the unallocated external hard drive to your PC, run EaseUS Partition Master Free.

First, Check file system error on the external hard drive

 

Step 1: Insert your SD card into your computer or connect your USB/external hard drive to your computer and run EaseUS Partition Master. Right-click the partition on your storage device and choose "Check File System".

Step 2: In the new window, keep the option "Try to fix the errors if found" selected and click "Start".

Step 3: Then EaseUS Partition Master will automatically check the file system error on your SD card, USB, or external hard drive. When it has done, click "Finish" to end the whole process.

1.  
2. 2. Right-click on the e xternal hard drive and select "Check partition", tick "Check Partition Properties", "Call Windows Chkdsk.exe" to fix found errors, "Surface Test".
3. 
4. This will fix bad sectors and internal errors on the external hard drive.

Next, create a partition on the external hard drive

 

Step 1: Launch EaseUS Partition Master

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

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

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

Step 3: Confirm to create a new partition

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

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.