Help! My external HDD suddenly became “unallocated”
Help me! I have my iomega external hard disk drive 500GB and it is full of files
and movies. It was working perfectly well yesterday. However, today suddenly became
an “unallocated” drive without even a drive name. I'm able to detect the
drive in the Disk Management but I have no way of accessing it.
Is there any way to fix my external HDD without losing files? I want to use my
HDD again and also don’t wanna lose those files.please help me, thanks a lot.
--Extracted from sevenforums
Analysis about hard disk showing unallocated
Are you facing the same issue? When trying to use the drives, it shows as unallocated
suddenly for no reason. What does this means? This means the data is there, but you
cannot access it. Before attempting to fix it, we need to figure out what makes hard
disk unallocated first.
There are many reasons that can cause hard drive showing as unallocated, and in many
cases not even an expert can figure out why it happened. But the most common reasons
Infection with a virus or spyware
Removing the hard disk improperly
Hard driver is outdated
Hard drive internal error
Detailed guide for hard disk unallocated repair in Windows 10/8/7
According to the possible reasons for which the hard disk shows an unallocated listed
above, here we offer a detailed guide to help you with hard disk unallocated
repair windows 10/8/7 correspondingly.
1. Download and run the anti-virus software to clean up viruses in PC
and external hard drive.
2. Removing or unplugging the external hard disk properly and carefully
3. Update the hard driver via Device Manager.
(1) Get to Device Manager by clicking on Start and typing in
devmgmt.msc or by going to Control Panel and
clicking on Device Manager.
(2) Right-click on the target disk under Disk drive, click on
Properties, then the Driver tab and then click
If this doesn’t work, you can also try to download the driver for your device from
the manufacturer’s website.
4. Check and fix hard disk internal error or file system error
If you tried every method listed above, but the hard disk still shows as an
unallocated space, you need to check and fix hard disk internal error or file system
error. Two methods are available for that.
A. Run CHKDSK
First of all, press Win+R at the same time to open
Run, input “cmd” and hit
enter (be sure to run it as a administrator). Then type chkdsk
f: /f /r /x.
f: refers the drive letter of the drive that you need to check
/f fixes the errors found in the F partition/volume.
/r locates the bad sectors on the drive and recover readable
data. But some data cannot be recovered with /r. So it is important to develop habit
of making schedule
/x forces the drive to dismount before the process starts.
B. Check and fix the hard drive error via AOMEI Partition
If you are not familiar with such computer administrating jobs, you can turn to a
third-party tool. AOMEI Partition
Assistant is highly recommended. It can run on Windows 10/8/7/XP/Vista.
With a neat and tidy interface, this software is quite easy to use for both computer
experts and newbies. To check and fix the hard disk error via AOMEI Partition
Assistant, do as follow:
(1) Download the freeware. Install and
launch it. Right-click the drive partition you need to check, and select Check
Partition under Advanced.
(2) Choose check partition and fix error in this partition by using
chkdsk.exe or other two options based on your needs. Then click on OK,
and wait until completed.
Bonus tips: you can also right-click the disk which shows as
unallocated space, and choose Surface Test to check whether there
is bad sectors on the hard drive.
If no error is found, you can repair the hard disk showing unallocated space by
creating a partition. But that will erase all data on the disk, so it is necessary
to recover the data from unallocated hard drive using a reliable recovery software
if you want to fix unallocated hard drive without losing data
To create partition, take the following steps.
(1) Run AOMEI Partition Assistant, right-click the unallocated space on the hard
drive and select Create Partition.
(2) Set the drive letter, size and file system of the hard drive as you wish and
(3) Back to the main interface, click Apply to commit the
Finally, the hard disk unallocated repair will be completed in Windows 10/8/7. So
don’t feel overwhelming next time when you encounter such errors. Besides repairing
hard disk unallocated error, AOMEI Partition Assistant easily deal with many other
hard disk errors, like USB drive showing
0 bytes, non-system
disk error, etc. Such a versatile is a “must” for anyone who always
wants to manage their disk or partition with ease. Most importantly, its Server edition provides
many more features you will need for effective disk/partition management on Windows
Server 2003, 2008 (R2), 2012 (R2), 2016 and more.