As is well known, we can divide our hard disk into multiple independent partitions, which can bring us great benefits.
Protecting data. With multiple partitions, we can leave a partition for operating system and one to store personal data. Therefore, if we are forced to reinstall operating system, our data will remain untouched and we will be able to access it.
Running multiple operating systems on the same PC. If our computer's hard disk has several partitions, we can install a new version of Windows on a separate partition without influencing the old one.
Improving Performance. Hard disk drives usually work better on smaller chunks of data rather than one big partition, and we can get a small boost in performance. For example, having a partition that is about 20%-30% the size of the total hard disk allows short stroking, meaning that the number of reading head repositioning delays (a performance consuming process) is greatly reduced.
However, though we can store different data on different partitions, certain partition might be inaccessible sometimes. And, there are a number of causes, including mistaken operation, computer virus invasion, physical damaged, and so on, which may result in serious problems. Next, we will analyze 10 different types of inaccessible partitions.
Under 10 Situations We Can't Access A Partition in Windows
1: Drive Letter Is Missing
Symptoms: after using computer for a long time, I suddenly find one of my partitions is missing in My Computer but I can see this space in Disk Management.
Here we can see the 90.65GB NTFS partition does not have a drive letter. Generally, if a partition is not allocated with a letter in Disk Management, it will be invisible in both My Computer and Windows Explorer. And there are several possible reasons for this issue: viruses remove the drive letter; system does not allocate letters for some special partitions, such as the system reserved partition; we remove this drive letter by mistake.
At this time, if we want to directly access this partition, we need to get the missing drive letter back. We can take the following operations to easily fix this issue:
Right-click the NTFS partition, then choose “Change Drive Letters and Paths” (can help add, change, and remove drive letter), and click “Add” and “OK” button.
As we know, most users are accustomed to storing valuable photos, business documents and personal files to computer hard drive. In this case, many users would like to hide a partition in which confidential files are stored because they don’t want others to access to their files without permission. However, once a partition is hidden, we are unable to see it in Windows Explorer, and we can’t turn to the function “Change Drive Letter and Paths” to fix this problem since this feature is always grayed out.
Here, in fact, the best solution is to unhide the partition by using third party program. And we take MiniTool Partition Wizard for example.
In the main window of the professional partition magic, right-click the hidden partition and then choose “Unhide Partition” button.
Then, set a drive letter for this hidden partition. Finally, click “Apply” button to perform all changes.
Thus, we can directly access files stored on this partition.
Some users may be unclear of the concept – RAW Partition. Actually, RAW partitions are disk partitions that have not been formatted with a Microsoft Windows NT file system, such as FAT and NTFS.
If we open the RAW partition, we may receive the following error messages.
1: You need to format the disk in drive H: before you can use it. Do you want to format it?
2: This volume does not contain a recognized file system. Please make sure that all required file system drivers are loaded and that the volume is not corrupted.
Please don’t format the partition immediately since this operation may cause data loss permanently. Here, before dealing with this issue, we’d better have an overall analysis of the probable reasons for RAW trouble. In general, there are many factors (virus invasion, system reinstallation, numbers of hard drives and partitions, and so on) contributing to RAW partition. To be specific, if the part of the hard drive partition table with partition information like partition starting position and ending position has been damaged or corrupted due to computer viruses, the corresponding partition will be given as a RAW file system.
To deal with this issue, we had better recover lost data from the RAW partition at first, and then reformat it. Well then, how can we recover data from RAW partition without affecting the original data? Here, if you have no idea of data recovery tools, try using MiniTool Power Data Recovery, which can help to recover 1GB data for free. Besides, this tool not only provides wizard-based operation and simple interface, but also can keep data safe all the time even in case of sudden power outages. Even a new user can easily recover lost data with this tool. For more information about RAW partition recovery, please see How to Recover Data from RAW File System, Partition and Hard Drive Efficiently.
After recovering data, we can right-click the RAW partition and then choose “Format…”. After that, we are able to specify File system as well as Allocation unite size, and add volume label for this partition. Then, click “Start” button to start formatting. During this process, we will receive a warning: Formatting will erase All data on this disk. To format the disk, click OK. To quit, click CANCEL. Here, we choose “OK”. Thus, all work has been done.
4: Partition Becomes Unallocated Space
It is believed that some users have encountered unallocated space. Here, let’s see an example from Tom’s:
Yesterday my external hard drive seems normal, and everything is fine, until there's a blackout and I have to put "Sleep" to my computer. After the power got back, the hard drive suddenly gone and when I check the list of drives under "Disk Management", it showed up as "Disk 1 - Unallocated".
Definitely, we are unable to access unallocated space. Unallocated space in disk refers to a kind of space which is not created with partition currently. They may have complete files, fragments and other files generated by some utility software and operating system. And, unallocated space emerges because of the loss of partition.
So well, Tom can turn to partition recovery tool like MiniTool Partition Wizard to recover lost partitions. For detailed to recover lost partitions, please see Partition Recovery.
5: Partition Is Not Accessible. Access Is Denied
Let’s consider a scenario: we stored massive data on F partition. However, we could not access this partition now and it said: "F:\ is not accessible. Access is denied".
This error message clearly indicates that the permission of this partition is corrupted. To fix this error, we need to try taking ownership of it.
1:Right-click the partition that we want to take ownership of, and then click “Properties”.
2:Click the “Security” tab.
3:Click “Advanced”, and then click the “Owner” tab.
4:In the Name list, click “user name”, or click “Administrator” if we are logged in as Administrator, or click the “Administrators” group. Note: If we want to take ownership of the contents of the folder, select the “Replace owner on subcontainers and objects” check box.
5:Click “OK”, and then click “Yes” when we receive the following message: You do not have permission to read the contents of directory folder name. Do you want to replace the directory permissions with permissions granting you Full Control?
All permissions will be replaced if we click “Yes”. Note: Drive name is the name of the drive that we want to take ownership of.
6:Click “OK”, and then reapply the permissions and security settings that we want for the drive and its contents.
6: Partition Is Not Accessible. The Parameter Is Incorrect
Consider the following scenario. When we try to access to files stored on our USB drive, we get an error message “The parameter is incorrect”. In this situation, how do we fix this problem?
In general, this error is of common occurrence that partitions on external hard drive, USB flash drive, SD card, etc. can't be opened and accessed. And, various factors can cause this issue. For example:
1:Power failure for powered hard drive
2:Plug out external hard drive or removable device in an improper way
4:Bad sectors on the hard drive
5:File system goes wrong, such as DBR, MFT, FAT.
In order to resolve this issue, we can try formatting this drive.
Step 1: Connect the drive to computer via USB port or motherboard.
Step 2: Right-click “Computer>Manage>Disk Management”.
Step 3: Right-click the corrupted drive and select “Format”. Click “OK” on the pop-up message box.
Step 4: Set Volume Label and File System and check the option “Perform a quick format”. Then click “OK” and the formatting will be done quickly.
Note: After formatting, we can open the drive and there is no error message, but files in the partition are removed.
Alternatively, we can also try the following option:
Step 1: Click “Start” button, type “cmd” and click “Enter”.
Step 2:Type command line “chkdsk /f /r drive letter:” and hit “Enter” key. Note: If bad sectors are found on the drive during the process, chkdsk will try to repair them. In that case, data stored on bad sectors will be lost.
In a word, although the above two methods can help to solve this problem, we had better recover all needed data stored on this inaccessible partition at first. Here, MiniTool Power Data Recovery can help us to easily and quickly recover lost data.
7: Shared Partitions Are Not Accessible From Other PCs
I have two Windows machines in my home environment, and I want to share data between them, including folders as well as partitions. I am able to connect to shared folders. However, when I try to open the shared partition, the following message appears: “\\ComputerName\Partition is not accessible. You might not have permission to use this network resource. Contact the administrator of this server to find out if you have access permissions. Access is denied.”
In this tutorial, we will show you how to solve this problem.
Firstly, open Windows Explorer and right click the partition which you have shared. Then, click “Properties”.
In the Properties window, go to the Security tab. Here you will see a list with the defined groups and permissions. If the group called Everyone is not listed, then you need to add it. If it is listed, you need to check the defined permissions and set it to at least Read & execute. To add the group, click “Edit”, and then click “Add”.
In the Select Users or Groups window, type “Everyone” and click “OK”. After that, click “OK” in the Properties window. Now you will see a window titled Windows Security. Wait until it disappears.
From now on, your shared partition will be accessible from other computers.
8: Partition Is Not Accessible. The File or Directory Is Corrupted And Unreadable
Have you ever encountered the error message (File or directory is corrupted and unreadable) when opening Windows partitions? And, you were unable to access data stored in this partition. This problem may happen to any of us. The direct consequence of the error is file loss since you are not able to access the partition now.
This error will occur if file, folder, MFT (Master File Table), or FAT (File Allocation Table) gets damaged due to certain reasons. Here, we can try using Chkdsk to check and repair file system error.
Step 1:Click “Start > Run”, type “cmd” and press “Enter”.
Step 2: Type “chkdsk /f drive letter:”, and then press “Enter”.
It may take a long time to finish the process, relying on the number of files and folders, disk speed, system resources, and capacity of the volume.
Note: Chkdsk, sometimes, may over-repair items, leading to difficulty for file recovery. Therefore, if there are some important data on this partition, we need to recover them at first and then use this tool to fix this error.
9: Partition Is Not Accessible, Data Error (Cyclic Redundancy Check)
In general, “drive is not accessible, data error (cyclic redundancy check)” is basically an error checking technique which is used for data verification. It is used by computers to specifically check the data stored in the hard drive or optical disks (DVD’s and CD’s). This error can be caused by either the operating system being corrupt, or a power loss.
To be honest, in this case, we have no choice but to turn to an effective solution to recover lost data. And, if the hard drive is physically damaged, please send it to a local data recovery service provider for data recovery.
10: Device Can’t Be Recognized
Have you ever encountered the following situation? Although we connected USB device to computer, nothing shows up in computer. And, there is an error: USB Device Not Recognized.
And, several factors could lead to this – USB data line problem, USB interface voltage instability, compatibility issue, BIOS setting problem and drive hidden issue. If we meet this issue, we can try using the following methods.
1.Connect the USB data line to another computer to check whether it is broken.
2.Check whether the USB interface voltage is adequate or not.
3.Check whether the motherboard and system are compatible with each other.
4.Make sure the USB is enabled in BIOS and operating system.
5.Try to unhide the drive with Disk Management or third-party tool.
After seeing the 10 different types of inaccessible partitions, you may get a basic understanding of this issue. However, if you want to recover data or transfer data out before doing any operations, detailed steps are shown below.
Inaccessible Partition Data Recovery
All in all, once partition or USB drive can’t be accessed or valuable data in it are missing, the first thing we should do is to recover lost data from this partition/USB drive. Here, MiniTool Power Data Recovery is a good choice for us since it has been awarded as the top 10 free data recovery software on TOPTENREVIEWWS.
This professional data recovery software provides five relatively independent data recovery modules which can masterly cope with data loss issues caused by various factors. It not only can help to recover data from hard drive partition, but also can recover data stored on USB flash drive, memory card, memory stick, and so on. Note: the free edition of this software can only help to recover 1GB data. If you wish to recover more than 1GB of data, you need to buy advanced edition.
Now, 10 situations where we can’t access a Windows partition as well as corresponding solutions have been listed. If you have any questions and suggestions, please leave your message below and we’ll reply as soon as possible. Thanks.