7 Solutions to fix Hard Drive Unallocated Error on Windows 10


Summary: Inaccessible data might be caused by the hard drive unallocated windows 10. The worse could be data loss. This page will help you with your problem. Read on!

Windows users should know that with an unallocated hard drive, it will be impossible to write, read and store data. Why? Without allocation, the user will not be able to use the space on the drive. Well, system installation will allow users to partition unallocated space – such space on your hard drive is yet to be assigned a drive letter. What we should do first is solve first the hard drive unallocated and recover data with Bitwar Data Recovery software.

8 major causes of hard drive unallocated

PC has a hard drive that may contain multiple partitions – allocating data conceptually. The unallocated space (unallocated partition) does not belong to a partition and no program can write to space. To utilize the unallocated space, the user needs to create a new partition with space or expand an existing partition.

Here are 8 reasons you need to know of hard drive unallocated windows 10:

  1. Hard drive internal error
  2. External hard drive physically damaged
  3. Error in File System
  4. Virus or malware attack
  5. Improper unplugging of a drive from the computer
  6. Outdated hard drive driver
  7. Created or modified the partition incorrectly
  8. Hardware failure

You might be asking, how to fix unallocated external hard drive without losing data? What can you do first? Save your files!

Recovery Data Before Everything gets Lost

Bitwar Data Recovery, a software tool most reliable in recovering lost, deleted and corrupted data. Here are quick steps you have to do:

Step 1. Select device or drive where you wish to recover your lost data

Step 2. Select a recovery mode and choose your target recovering file types (e.g. document or photo)

Step 3. Scan and preview the data, then hit the recover button and save the data into different device or partition.

There you have it, your files are now safe, and you may now proceed on how to recover unallocated hard drive.

6 Solutions to fix Hard Drive Unallocated Error

Solution 1. Solve Hard Drive Unallocated Windows 10  with Control Panel

Step 1. Open Control Panel by entering “Control Panel” in the search box of the Start Menu.

Step 2. Go to the Administrative Tools window.

Step 3. Select the Computer Management icon. Click Disk Management.

Step 4. Right-click the unallocated hard drive.

Step 5. Choose New Simple Volume from the pop-up menu. Click Next.

Step 6. Use the Simple Volume Size in the MB text box as the size of the new volume. Click Next.

Step 7. Choose a drive letter for the new volume. Click Next.

Make sure the option Format This Volume with the following setting is chosen.

Step 8. Select NTFS as a file system. Click Next.

NOTE: The process may take some time depending on the size of the volume. The assigned drive letter to the new volume will only appear once formatting is finished. Lastly, the capacity of the new volume might not be the same as previous due to the utilization of some bytes during the formatting process.

Solution 2. Solve Hard Drive Unallocated Windows 10  with CMD and Disk Management

So how to format the unallocated disk using cmd? Follow the steps below.

Step 1. Go to Diskpart and type “list volume” and press Enter.

Step 2. Type “select volume [drive letter]” and press Enter. (the ‘drive letter’ is the letter assigned to your unallocated hard drive.

Step 3. Type “delete volume” and press Enter.

Step 4. Type “list volume” and press Enter.

Note: Step 4 to Step 7 is only for sometimes Disk Management cannot create a new volume, proceed with the steps. If you can, skip these steps and jump to Step 8 after performing Step 3.

Step 5. Type “select volume [drive letter] and press Enter.

Step 6. Type “delete volume” and press Enter.

Step 7. Type “delete volume override” and press Enter.

Step 8. Click Disk Management and right-click your unallocated hard drive to create a new volume. Set the file system of the unallocated hard drive.

 You may now try to save data in the hard drive.

Solution 3. Solve Hard Drive Unallocated Windows 10  by Expanding Partitions

How to recover unallocated space in the hard drive in windows 10? If you cannot create new partition unallocated space windows 10, you can also expand the existing partition to utilize the unallocated space. Follow the steps provided below:

Step 1. Go to Control Panel > Disk Management.

Step 2. Right-click existing partition and select Shrink Volume.

Remember: in expanding the existing partition; you can only utilize the physically adjacent unallocated space.

Solution 4.  Solve Hard Drive Unallocated Windows 10  by Running Anti-Virus Software

To determine whether the unallocated hard drive is caused by virus attack, run the anti-virus software on the unallocated hard drive.  

Solution 5.  Solve Hard Drive Unallocated Windows 10  by Updating Hard Drive Driver

To check if the driver of your hard drive is outdated, follow the steps below:

Step. 1. Open “Device Manager” by entering “Device Manager” in the search box of the start menu. Click Enter.

Step 2. Your unallocated hard drive is in yellow alert. Right-click the hard drive and select Update Driver.

Step 3. Choose Search automatically for updated driver software.

Remember: If Windows has no new driver, device manufacturer’s website and simply follow the given instructions.

Just in case the above steps did not work out, reinstall the driver.

Step 4. Go to Device Manager and right-click the name the hard drive and choose Uninstall.

Step 5. Restart PC so Windows can reinstall the driver.

Solution 6.  Solve Hard Drive Unallocated Windows 10  with CHKDSK

To check and also try fixing the unallocated hard drive, follow these steps:

Step 1. Run the progress administrator by pressing the Win+R and type “cmd.” Click Enter.

Step 2. Type chkdsk [drive letter]: /f/r/x.

Note: type the drive letter assigned to the unallocated hard drive. The corresponding letters are commands to fix the drive. /f – fix error in the drive, /r – locate bad sectors and recover readable info, /x – dismounts the hard drive before the process starts.

If there is no detected error in the hard drive by running the CHKDSK, the error might be a file system. With this, recreate the partition on the hard drive unallocated windows 10.


We hope that this article has helped you how to fix unallocated hard drive windows 10.

This problem is also dominant in a USB drive, pen drive, SD card and memory card showing unallocated in PC. The key to solving unallocated hard drive windows 10 is finding the reason behind the problem. Fixing this might be impossible but performing a few steps can do.

To save files ahead of disaster, download and install Bitwar Data Recovery. It is recommended to recover the data first before performing several solutions.

Download for PCDownload for Mac

Read More

  1. Quick Fix for External Hard Drive not Showing up Windows 10
  2. Quick Fix on How to Repair Hard Disk Not Detected By Computer
  3. Best Solutions to Fix Windows was Unable to Complete the Format
  4. 6 Methods to Fix You Need to Format Disk in Drive Before You Can Use It
  5. 2018 Best Solutions to Fix SSD Not Showing Up on Windows
  6. How to Fix “Hard Drive Only Shows Half Capacity” error

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  1. I did all the possible solutions declared above but nothing happened. Ive been had this issue many times and i can easily fixed them but this issue of mine today is worst i dont know why all solutions i did are not working. My hard drive 1 still unallocated and unable to utilized and it still shown on grayscale. Cant format, cant delete partition, updated driver, cant create new partition, all solution commands using cmd not works, i used different recovery softwares and disk utilizing or extender softwares, diskchecking, troubleshoot all parts dissambled and assembled. Im using new acer aspire windows 10 500gb hdd drive 0 54gb and unallocated drive 1 is 442gb they are separated and unable to merge. Thats why i can only use the 54gb of drive 0. This is sad and never thought i would face this f….n problem in new laptop maybe the reason that i got rejected nad sector hdd even its new. Im crying now.. Huhuhu

  2. Exactly right, the capacity of the new volume might not be the same as previous due to the utilization of some bytes during the formatting process.

  3. Got a recommendation of the software for different issues (from a laptop, an SSD and a pen drive), including this one, I honestly left all those things to get dusty since I couldn’t fix it, software did all of that very fast, simple and didn’t need help of anybody else, thank you very much, life time client!

  4. Indeed, first step of all is just putting everything in a safe place, so is the same about computers and files, save your files, then try to fix it while you can. Pleasant experience with Bitwar, highly recommended for non experience users since is so intuitive.

  5. Oh boy! Though this was going to be way more difficult than it was! Seems like the problem is fixed. Maybe you could guys also make some articles about how to prevent this type of things happening, like how to keep a healthy computer? does that sound too crazy? haha. Anyways, thank you for your article, was truly a salvation to me, thanks!

  6. the issue, so I’m assuming that it was because of the creation of the partition incorrectly. I used Bitwar to restore the files and create the backup, then format all over again and create the partition again. Just wanted to said that is doable, pretty easy to fix, so everybody should try it!

    • Thanks for sharing your experience with us! Jack, that’s also an excellent thing that you can fix the issue finally. Anything, we are always here to give support to you, try to send us an email or leave questions here, we will back to reply you ASAP. Have a nice day.

  7. The most efficient, reliable and easy to use software for recovering files! There are many other softwares trying to fix the same issues, but this one is incredible easy to use, also a very important information: the support you can have from the online chat is amazing, highly recommended to anybody, even if you are like me who doesn’t get along with computers, I was using the chat in the phone to be sure I was doing every step correct and everything worked out great 5/5

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