Has your external hard drive suddenly become unallocated on your Windows 10 device? Do not worry, you can easily fix this issue, without losing any data. In this blog, we will discuss the ways to recover files from unallocated hard drives in Windows 10. So, without further ado, let’s get started.

Using Command Prompt

You should pursue these directions provided below:

Hit the Windows and R buttons over the keyboard to invoke the Run dialog box.
After that, input ‘cmd’ into it and hit the Enter button to launch the Command Prompt.
Once you reach the Command Prompt screen, input ‘diskpart’ then hit the Enter key.
You should input ‘list volume’ then press the Enter key.
Select the drive letter via the pursuing command: select volume z.
Now, input the following commands:
delete volume
list volume

Make a Fresh Volume Manually
You should follow these directions provided below:

First of all, insert the following commands into the Command Prompt and hit the Enter key after each line,
select volume z
delete volume
delete volume override
Go to the Search section.
Then insert ‘disk management’ in it and hit the Enter button.
You should choose the ‘Create and format hard disk partitions’ option through the results.
Go to the unallocated hard drive and right-click on it.
You have to choose the ‘New Simple Volume’ option and select the Next button.
Navigate to the ‘Simple volume size in MB’ and set it, then click on the Next button.
You should choose the ‘Format this volume with the following settings’ option.
Thereafter, change the File system to NTFS and ‘Allocation unit size to Default’ then give a name to the Volume label.
Later, check the box of ‘Perform a quick format’ and click on the Next button.
Now, select the button of Finish.
Using CHKDSK

You should follow these directions provided below:

Go to the Windows icon and click on it to launch the Search section.
Then, insert ‘cmd’ into it and select the OK button to open the Command Prompt.
You should choose the Command Prompt, and right-click on it, then select the ‘Run as an administrator’ option.
Once you reach the screen of Command Prompt, insert ‘chkdsk z: /f/r/x’ and press the Enter key.
Updating the Hard Drive Driver

You should pursue these directions provided below:

Hold the Windows and R buttons simultaneously to launch the Run dialog section.
Thereafter, input ‘diskmgmt.msc’ and select the OK button.
You should select the ‘Disk drives’ option and expand it.
Then choose the unallocated hard drive, and right-click on it.
Choose the ‘Update Driver Software’ option.
After that, select the ‘Search automatically for updated driver software’ option and follow the on-screen steps.
Now, reboot the system.
By following the steps mentioned above, you can fix the unallocated hard drive issue on your Windows 10 device.

SOURCE:- How to Fix Unallocated Hard Drive Without Losing Data on Windows 10?