Recovering Unallocated Space of a USB Flash Drive: Top Solutions 2025

Why does a USB Flash Drive Become Unallocated Space?

USB flash drive is a popular and portable way to store and transfer data, widely used in daily work and life. However, it is not immune to occasional issues—for example, a USB drive may suddenly become unallocated space, making the data stored on it inaccessible.

So, what causes this problem, and more importantly, how can you fix it and recover files from the USB drive? Before jump into solutions, it's important to understand why this issue occurs:

• Accidental deletion of the partition
• File system corruption due to unsafe removal
• Virus or malware attacks
• Failed formatting or interruption during write operations
• Bad sectors or hardware failure

Once the USB flash drive becomes unallocated, Windows won’t assign it a drive letter, and you won’t be able to access the data directly in File Explorer. However, this doesn’t mean your data is lost forever. You still have a good chance of recovering unallocated space of a USB flash drive using proper methods.

How to Recover Unallocated Space of a USB Flash Drive

Recovering unallocated space of USB flash drive on Windows 10 and 11 mainly involves three steps: recovering data, creating a partition, and moving data. Once a USB drive becomes unallocated space, you should stop using the drive immediately to avoid data being overwritten.

Step 1. Recover Files from Unallocated Space of USB Drive

There is no doubt that the first thing to do is definitely to recover data from the USB drive with unallocated space. Incorrect operations may lead to permanent data loss that cannot be recovered. Since Windows cannot access files in unallocated space, the professional data recovery software MyRecover comes in handy at this point.

MyRecover features a user-friendly visual interface that simplifies the data recovery process, allowing even computer novices to independently complete data recovery with just a few clicks on icons. Here's how:

1. Download and install MyRecover on your computer from secure channel. Connect the unallocated USB to the computer via a functional port.

2. Launch it and select "Partition Lost Recovery" under the "Advanced Recovery" section, the unallocated USB flash drive will be displayed. Then select the lost partition and click "Scan" to start the process.

3. Choose the files you wish to recover from the recoverable lists and click "Recover".

4. Select a safe location (not the original one) to save the recovered files.

Upon the completion of the recovery process, the message indicating recovery successful will pop out. You can check and access the recovered files by clicking the destination folder path or "Browse".

Step 2. Fix Unallocated USB Flash Drive Without Losing Data

After successfully recovering your data, the next step is to fix the unallocated USB drive so that you can use it again. You can make unallocated space usable by creating a new partition with the following two ways. Let’s go through the process of how to fix unallocated hard drive without losing data in Windows 10 or 11.

Option A. Create a New Partition with Disk Management

In Disk Management, you can manage all your disks and partitions including the unallocated USB drive. Insert the unallocated USB drive into your computer, follow these steps to create a new partition:

1. Press "Win + X" and choose "Disk Management".

2. Select the unallocated USB drive and right click on it, then choose "New Simple Volume".

3. Set the size for the new volume and click "Next".

4. Choose a new and different drive letter from the drop-down menu and click "Next".

5. In the format partition window, choose a desired file system and check the "Perform a quick format" option, then click "Finish" to complete the process.

Option B. Create a New Partition with Command Prompt

Besides, you can use Command Prompt to create a new partition. Here's how:

Open "Command Prompt" and run it as administrator. Then type the following command to create a new partition.

Diskpart: open diskpart.

List disk: list all available volumes on the computer.

Select disk 1: select the volume 6 to create new partition. (Replace the number "1" with your actual disk number.)

Clean: erase all data on the disk.

Create partition primary: create a new partition on the selected volume.

Format fs=fat32 quick: perform a quick format and format the selected volume to fat32 file system. You can replace "fat32" with any file system if you like.

Assign letter=K: assign a new drive letter. (Replace the drive letter "K" with any available letter.)

Exist: exist the DiskPart.

Step 3. Move Recovered Files to New Partition

After creating a new partition, your USB drive will become usable again. Now you can move all the data recovered with MyRecover to the USB drive. Once done, check again to avoid missing any important data.

FAQs:

1. How to recover data from unallocated space?

To recover data from unallocated space, you need to use professional data recovery software like MyRecover, since the operating system can’t access files on unallocated volumes directly.

2. How to repair an unrecognized USB flash drive?

When a USB flash drive is unrecognized, it might not appear in File Explorer, though it may still show up in Disk Management. Similar to unallocated partition, you’d better recover the data on it first, and then solve the unrecognizable issue through methods such as updating or formatting the USB drive.

3. How to fix an unallocated disk without losing data?

As mentioned above, first, use professional data recovery software like MyRecover to recover the data, and then create a new partition using Disk Management or Command Prompt.

Summary

Recovering unallocated space of a USB flash drive can be exasperating, but the situation is often recoverable. Remember that recovering data is always the top priority, then try to fix the unallocated USB drive. When a drive unreadable on computer, professional data recovery software such as MyRecover can effectively help you recover data from the inaccessible drive.

MyRecover is capable of covering various data loss scenarios, such as deleted partitions, formatted USB drives, emptied recycle bins, etc. Unlock advanced capabilities like pre-recovery file previews and unlimited data recovery quota—upgrade to MyRecover Professional edition today.