Note: To fix the disk not initialized and unallocated issue, take Solution 1 - Solution 3. Apply Solution 4 - 6 to solve disk is not initialized and shows nothing about disk capacity. You may follow the quick guide:

Disk 1 Is Unknown Not Initialized

"When I plugged in my external hard drive, Western Digital My Passport 0740 (500GB), PC said that it's successfully installed however it did not appear on My Computer. Also, when I went into system tools, it said disk 1 is unknown, not initialized, and unallocated. Does anyone know how to recover data when a hard drive is not initialized or how to initialize disk without losing data?"

Disk Not Initialized Symptoms

Like the case above, the disk unknown not initialized issue usually occurs unexpectedly in all the Windows versions, including Windows 10, 8, and 7, and it annoys users. When the issue occurs, your external hard drive may show "unallocated space" or nothing about the disk capacity in Disk Management (as shown in the image below), so you cannot open and access the data on this disk.

Disk Unknown Not Initialized

Causes of Disk Unknown Not Initialized

Although the disk shows unknown and not Initialized in both situations, they present different information about the capacity of the hard drive, which means they are caused by different reasons.

If disk unknown not initialized is accompanied by unallocated, the likely cause is MBR corruption on the hard drive. MBR, which stands for Master Boot Record, is the first sector on an MBR or GPT disk. It provides information on loading Windows and on the partition of the disk. Thus, when it is corrupted, you will certainly encounter issues, including the disk showing as not initialized.

However, if your disk 1, disk 2, or another disk becomes Not Initialized without any details about the disk storage, the causes are connection issues, disk driver issues, and physical corruption on the disk.

How to Fix Disk Not Initialized in Practical Ways (Video Tutorial)

Watch a video tutorial on how to fix disk unknown not initialized problem. Key methods in this video are:

  • 01:39 Clean the selected disk
  • 01:56 Create partition primary
  • 02:57 Format the disk to NTFS 
  • 03:22 Remove CMOS battery
  • 03:32 Check for updated drivers

How to Fix Disk Unknown Not Initialized in Windows 10/8/7

Depending on your situation, you may have to use an appropriate solution for the disk not initialized issue on your computer, be it a local hard drive or an external hard drive.

To fix a disk from turning into not initialized in such a case, you can initialize the disk directly. Then comes the question - does initializing a disk erase data? Actually, initializing a disk will rebuild the master boot record. It WON'T ERASE the data on the disk. However, to make the disk usable again, you need to further partition and format the disk, which will erase the files on your hard drive. Thus, to fix the disk not initialized, you need to:

  • Initialize the hard drive
  • Recover data from the disk and create new volumes
  • Partition and format the disk to make it ready for data storage

Solution 1. Initialize Disk

Applies to: Fix disk is not initialized and shows unallocated.

This is the easiest way to fix the disk unknown not initialized issue. This also works to initialize a brand new hard drive.

Step 1. Right-click "My Computer" > "Manage" to run Disk Management.

Step 2. Here, right-click the hard drive and click "Initialize Disk".

Step 3. In the dialogue box, select the disk(s) to initialize and choose MBR or GPT partition style.

Initialize the hard drive to fix disk unknown not initialized error

After initializing the disk, you can now recover data from your disk. Based on your needs, you can recover data only from the disk or recover both the partitions and the files.

Solution 2. Recover Data from Hard Drive and Create New Volumes

Applies to: Fix disk is not initialized and shows unallocated.

Here, if you have important files on the external hard drive, you can try the hard drive recovery software - EaseUS Data Recovery Wizard to recover the files from the inaccessible disk.

This powerful data recovery software can restore files from disks in different states, including recover data from dead hard drive.

 Download for Win Recovery Rate 99.7%
 Download for Mac Trustpilot Rating 4.6

Step 1. Select and scan the lost partition

Launch EaseUS Data Recovery Wizard, select "Lost Partition" and click "Scan" to search for all the lost data. If there are many lost partitions, you can identify them through its partition size.

Note: Since the Windows system doesn't support the Linux file system, the Ext2 or Ext3 partition will be recognized as lost partition with no drive letter in the software. If you want to recover data from Ext2/Ext3 partition, you can follow these steps.

select the lost partition to scan

Step 2. Filter the scanned results

Because there will be a lot of scanned files, you can choose a file category for quick filtering, such as Pictures, Videos, Documents, Audio, and Others. Or if you remember the file name, you can just look it up in the search box in the upper right corner.

check all found files

Step 3. Preview and recover data from the lost partition

Before recovery, you can preview the file to make sure it is the data you need. Choose all the files you need and click "Recover" to restore them. 

recover files from lost partition

If you only recover data, you must partition the disk by yourself following the steps below.

Step 1. Right-click "This PC" and choose "Manage" > "Disk Management".

Step 2. Right-click the unallocated space and choose "New Simple Volume..."

Step 3. In New Simple Volume Wizard, click "Next" to continue.

Step 4. Follow the wizard to specify the volume size, assign a drive letter to the volume, and then format the partition.

Disk Not Initialized - Partition the disk

If you don't want to create partitions by yourself, you can recover partitions on your disk that shows "Not Initialized", which will help you restore the original partitions on the hard drive.

Solution 3. Perform a Partition Recovery 

Applies to: Fix "disk is not initialized" and shows "unallocated".

Download and launch the reliable partition tool - EaseUS Partition Master, on your computer. With it, you can recover the partition on your hard drive with ease. Besides, you can also rebuild MBR to try to fix the disk unknown not initialized problem.

Step 1. Open EaseUS Partition Master and click "Partition Recovery". Select the target disk with your lost partition and click "New Scan".

partition recovery step 1

Step 2. Wait patiently to let the software execute "Quick Scan" and "Full Scan" operation. It will mark your deleted partition as "lost" as the Status section. Select the lost partition, and click "Recover".

partition recovery step 2

You can also double click on the partition you're looking for to preview its content and click "OK" to confirm.

partition recovery step 3

Step 3. Wait patiently and click "Done" when the partition recovery process completes.

partition recovery step 4

Situation 4. Check Disk Connection

Applies to: Fix disk is not initialized and shows nothing about disk capacity.

Minor connection issues can cause serious problems like the one discussed above. To check your disk's connection:

  • Connect your external hard drive to another USB port, including the rear ones, on your computer
  • Use the original cable to connect your hard drive
  • Use another cable to connect your external hard disk
  • Connect your external hard drive to another computer

Situation 5. Update Device Driver

Applies to: Fix "disk is not initialized" and shows nothing about disk capacity.

An outdated or corrupted disk driver may also be the culprit. In this case, you can update the device driver with Device Manager.

Step 1. Right-click on "This PC" (in Windows 10) and choose "Properties".

Step 2. Click "Device Manager" then expand "Disk drives". Find and right-click the problematic disk and select "Update driver"

Step 3. Click "Search automatically search for driver software online".

Step 4. Wait for the driver to be updated, then reboot your computer. Afterward, you can try to reconnect your USB drive to the PC and check whether the USB drive shows up or not.

Disk Not Initialized - Update Device Driver

Situation 6. Send for Manual Repair

Applies to: Fix disk is not initialized and shows nothing about disk capacity.

Physical damage will inevitably result in serious issues on a storage medium, including disk unknown not initialized. If the methods above fail to solve the problem for you, sending your device to professionals for manual repair is a good choice.

Extra Tip: How to Fix Cannot Initialize Disk in Windows

A common reason that leads to disk unknown not initialized is that you fail to initialize the drive with a message saying the request could not be performed because of I/O error appears. This causes your disk to be shown as unknown or not initialized.

When you can't initialize a hard disk, disk unknown not initialized is not the only issue you encounter. For detailed explanations and corresponding solutions, head to our article about how to fix the i/O device error.

If the guide didn't help you solve the problem, you are highly recommended to seek help from experts for manual repair or directly replace the disk with a new one.

The Bottom Line

Although initializing a disk won't erase data on the device, further operations will. Thus, if you want to fix a disk that is not initialized without losing data, data recovery software is needed. However, if your disk shows unknown, not initialized due to physical corruption, no data recovery software will help, and only manual data recovery services have the chance to rescue your files.

FAQs About Disk Is Not Initialized

Get more information on the disk not initialized problem. 

1. How do I fix disk 1 unknown not initialized?

As outlined in this guide, there are basically 6 ways that can help you fix disk unknown not initialized error. They are:

  1. Initialize the disk with Disk Management
  2. Recover data from the unknown hard drive and create new volumes.
  3. Perform partition recovery from the unallocated & not initialized drive.
  4. Check the hard drive connection
  5. Update hard drive driver
  6. Send the hard drive for manual repair.

For detailed instructions, you can refer to the main content on this page and try any method to make your disk work again.

2. How do I force a hard drive to initialize?

For a new hard drive, you may directly follow the steps below to initialize it. 

As for a used hard drive, you may need to copy or back up all saved data to another device first. Then, use Disk Management to delete all existing partitions. Then, continue with the following steps to initialize the drive:

Step 1. Open Disk Management.

Step 2. Right-click the not initialized HDD/SSD and select "Initialize Disk".

Step 3. Select the disk to initialize in the dialog box and set the disk partition style as MBR or GPT.

3. Will initializing a disk erase it?

Does initializing a disk erase data? Solely initializing a disk won't erase its data. But, to use the disk, you need to further partition and format the disk, which will cause data loss.

Therefore, if you don't want to lose files stored on your hard drive, using data recovery software is necessary. You may refer to recover data from unknown not initialized hard drive for detailed instructions. 

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Updated by Cedric

Cedric Grantham is one of the senior editors of EaseUS who lives and works in Chengdu, China. He mainly writes articles about data recovery tutorials on PC and Mac and how-to tips for partition management. He always keeps an eye on new releases and likes various electronic products.

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Approved by Mahesh Makvana

Mahesh is an experienced computer tech writer. He's been writing tech how-to guides for about 8 years now and has covered many topics. He loves to teach people how they can get the most out of their devices.

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