"Disk is not accessible. Access is denied" error
The Windows operating system displays such an error message for volumes with corrupted metadata.
When you try to open such a volume, the operating system reads certain sectors of the disk,
in which it expects to find metadata about the volume: where it starts on the disk,
what size it is, what file system used on the volume, starting sector for the root directory of the volume and the like.
If an error occurs when reading any of these metadata records
(it is rather not about physical failures of the mechanical parts of the disk,
but about logical failures caused by incorrect metadata), then access to the data on the volume will be denied.
Often Disk Management lists RAW as the file system for such a volume.
There are several ways to solve the volume access denied problem.
- Take the disk on which the damaged volume is located to a data recovery service.
- Try to restore access to the volume yourself using special data recovery software.
- Try to understand what exactly is damaged in the metadata and fix it, for example, by taking data from backups.
The table below compares these approaches according to the main criteria.
||Risk of further damage
||Time to data
||Try something else?
||Requires special knowledge?
|Take disk to a service
||Most likely yes8
|Data recovery software
||From a couple of minutes to several days5
||Average from 60 USD7
1 - It depends on the degree of professionalism of the company's employees.
The most important rule when recovering data in a service is to never work with client's data storage.
Service employees must create a disk image and give the disk back to the client.
Only in this way it is guaranteed that there will be no further damage to the disk and the data on it.
2 - Such software usually works in read-only mode,
which means that using the software does not lead to logical damage of data on the disk.
It is worth noting that in the case of a physically "sick" disk, even reading can lead to further mechanical destruction.
In such cases, with the help of data recovery sowtware, you can make a disk image file and then work with it.
Read here how to make a disk image for free.
3 - This is the most dangerous method, since it directly writes to sectors on the disk,
which means that both metadata and user data can be overwritten.
4 - As a rule, the service will not start dealing with your case immediately,
creating an image takes time, which means you should not expect to receive data on the day of the call.
5 - The time here is determined by the size of the disk from which you need to recover data,
as well as the way it is connected to the computer.
The larger the drive and the slower the connection (USB is the slowest, SATA is the fastest),
the more time is needed. A 64 GB flash drive can be scanned to the end in less than an hour,
and a 2 TB drive will take about 14 hours.
Interestingly, data recovery software uses algorithms which can quickly enough find out where the file system records
are most likely located, which means that you can see files and folders in just a few minutes after the scan starts.
6 - If you manage to guess what exactly is wrong with the metadata records and edit them
so that the operating system recognizes them as correct and opens the data volume,
then the result will be instantaneous. If it is not immediately obvious what is wrong,
then you need to examine the metadata records and try different options, which is generally unpredictable in time.
7 - It is worth noting that there are also free solutions,
but they, as a rule, do not restore the tree structure,
and the files are extracted without original names,
so we do not consider such tools here.
8 - Again, it all depends on the professionalism of the service employee,
if everything is OK, then your disk will be with you, and they will work with a copy.
Once you have the disk, you can try as many options as you like.
9 - You can get so carried away with editing metadata that even data recovery software can't do anything afterwards,
because they still rely partially on file system metadata.
10 - It should be noted that when you contact a service,
you pay for the work itself, that is, the service uses data recovery software,
but this software does not belong to you, and the next time you should pay the service again.
In the case of purchasing data recovery software, you can do as many future recovery as you need.
Here you can find a detailed comparison of the best data recovery software.
It is useful to read how to choose the best data recovery service.
Editing Basic Metadata on an NTFS Volume.
How to fix a FAT volume by editing metadata.
Still have questions?