“I’ve plugged a external hard drive on my Windows 7 and Windows 10, both have the
same situation that the device has been detected, but isn’t shown on explorer. Thus,
even the external hard drive recognized, the files can’t be accessed. But I really
need to access to it for the important photos and documents. Is there any one can
help me? Any help will be appreciated in advance.”
Why it happens?
One of the most common error messages that make the hard dive inaccessible is “Hard
drive is not accessible. Access is denied”. Well, there are many reasons would cause
external hard drive recognized but not accessible. Like the following reasons:
1. The external hard drive may be a new drive without any partition on. If the
external hard dive is a brand-new hard drive, and there is no partition on the
drive, the system cannot recognized the drive size, which would cause the hard drive
detected but not accessible.
2. It is too old of your driver software. You may find your external hard drive
recognized in Device Manager, but not in Disk Management.
3. Encrypt external hard drive with Bitlocker. If you use Bitlocker to encrypt
your hard drive, you may meet the problem that external hard drive recognized but
not accessible and your important files cannot be used.
4. Besides, there are many other reasons could cause your external hard drive
inaccessible, like hard drive broken, the USB power supply of removable device is
How to solve external hard drive recognized but not accessible?
To avoid data loss, you should backup the external hard drive before any operation.
As for so many different situations would cause the error occurred, you may try more than one solution to fix it. If you get the error message that “The hard drive is not accessible. Access denied”, you can try the following solutions for solving different situations.
Solution 1: for the new hard drive without any partition
If you meet the problem that cannot access the external hard drive, you can open
Windows Disk Management to see whether it is a new hard drive without any partition.
If there is no partition on the hard drive, then, you can partition hard drive,
so that it can be accessed normally.
* If this could not solve your problem, you can fix the error with next solution.
Solution 2: for driver software not update
If your external hard drive (USB flash drive) is visible in Device Manager but not in
Disk Management, and you cannot access the external hard drive. Then you can try to update the USB flash drive driver to see if it
1. Open “Computer”, select “System Properties”.
2. Click “Device Manager” -> “USB Controller”, click “+”, and you will
see a yellow exclamation mark.
3. Right click it and choose “update driver software”, click “automatically
search for drive software online...”
Wait the update progress and let the driver to be installed, and then, reboot the
computer. Then, reconnect the USB drive to the PC and check whether it can be
Solution 3: for hard drive errors
If your external hard drive is suddenly no longer operational on your computer, you
can make use of the error
checking tool to overcome this problem by navigating to Properties ->Tools -> Check Now. If you are fortune, your hard drive may be accessible after
checking. On the contrary, you may still get the error message “hard drive is not
accessible. Access is denied”.
Solution 4: for BitLocker Drive Encryption
If you cannot access the external hard drive because of the BitLocker Drive
Encryption, then, you need to change the BitLocker Encryption Service.
1. Press Win + R simultaneously, typeservices.msc, hit Enter. It will open the local
2. Here, Find BitLocker Encryption Service, double-clickProperties.
3. In the Properties page, change the Boot Type into AUTO, clickOK.
4. Reboot BitLocker Drive Encryption Service.
Thus, you may access your external hard drive.
Solution 5: solve hard drive inaccessibility issues by formatting
To solve external hard drive recognized but not accessible problem, formatting will be the sure shot way. If all above ways cannot solve the external hard drive is not accessible problem, you should format it. However, you may face the big problem that formatting will cause your data loss permanently. Fortunately, you can try to use the free hard drive data recovery tool iBoysoft Data Recovery to recover data from inaccessible hard drive. Once your files are recovered, you can access your data again. So, you can go ahead to format the inaccessible hard drive without worrying about data loss.
To format external hard drive, here we highly recommend you a hard drive format tool AOMEI Partition Assistant Standard, which
allow you to format external hard drive easily ad simply. And here you can learn how
to format external hard drive with AOMEI Partition Assistant.
Step 1. Connect the external hard drive to your PC, make sure
it can be detected.
Step 2. Free download AOMEI
Partition Assistant, install and launch it.
To format the inaccessible drive, here
you need to right click it, select Format Partition.
Step 3. Then, it will pop up a small window where you can set
up the detailed of formatting. You can format the external hard drive to FAT32,
NTFS, exFAT, Ext2, Ext3, etc. Choose one and click OK.
Step 4. When you back to the main interface, click Apply-> Proceed.
After the formatting, you may reuse the external hard drive as a new one.
* AOMEI partition Assistant has specific edition for Windows Server users. If you are
Windows Server users, you can turn to AOMEI Partition Assistant
Server for help.
Solution 6: for the external hard drive is visible in Windows Explorer but cannot be accessed
Another way is to reset the permission from Windows Explorer if it is visible in
Windows Explorer but you cannot access it.
1. Right click on the inaccessible drive, select Properties.
2. In the Properties window, select Security, click on Edit...
3. It will pop up a window “Permissions for New Volume” dialog box. Click
the Add button to continue.
4. Then, add a new user maned “Authenticated User” and click OK.
5. From the permission section, give “full control” to newly added user and
6. The dialog box will show two options: “Continue” or “Cancel”.
7. Press Continue… and Cancel at last.
Now, you are done, and you can reboot your computer to check whether you can access the external hard drive successfully.
This article provides different solutions for different situations of “external hard drive recognized but not accessible. Actually, there are more than one error for hard drive is not accessible. You may meet many other errors such as “Drive is not accessible. The parameter is incorrect”; “Drive is not accessible. The volume does not contain a recognized file system”. “Drive is not accessible. The disk structure is corrupted and unreadable” etc. If you have any great solution or any new question, welcome to write to our comment area. We can fix it out together.