How to Recover USB Pen Drive Lost Space in Windows (No App)

Last Updated: January 9, 2017

Pen Drives are very handy to store and transport data in many situations. After using for some particular purposes, we might have been seeing that the capacity is reduced to a bare minimum around in the ranges of few MB.

This can be recovered in Windows without installing any specific formatter utility to your system. It is a multi step process and requires some attention while doing the recovery. Here we will see how to recover the lost space from a 16GB pen drive using Windows 10.

Fed up with a slow computer and planning to switch to SSD drive for your Windows or MAC, please refer SSD Buying Guide before you pay for SSD drive.

If the Pen Drive is losing space only after usage of some particular applications, then it can be recovered easily. For example, a 16GB pen drive after using for recording in the Set Top Box may become ~200MB available while using with a Windows PC. Mostly this situation occurs during reformatting the Pen Drive according to the specific devices we use it.

Related: How to find out missing Hard Drive Space on Windows?

Here, the STB recorder is running with Linux or similar OS so that while using the Pen Drive it will reformat the drive according to its file system. After that, if you plug that Pen Drive into a Windows PC then it will be formatted to the rest of the available space for Windows File Systems.

This is eventually appears as losing space in Pen Drive after some special usage. This can be recovered easily by reformatting the Pen drive using the below procedure.

Step 1: Analysis of the Pen Drive

To start with, we need to confirm the Pen Drive is having the original space. For that, Plug the Pen Drive into your PC and open “Disk Management” utility. In Windows 10, you can open this by right clicking on Start Button and selecting “Disk Management”. It will show the available disk drives connected to your PC. In that, Pen Drive will be displayed as Removable Drive with some drive letter. Confirm that your Pen drive is having the original Capacity. If it is not, then this process should not be applied and may be tried with any low level format options.

recover pen drive lost space

If the Pen Drive shows the full capacity in the Disk Management, then check for the partitions it having. Mostly we will be finding some active partition with some other types of File system. Now note down the currently attached drive letters for all partitions and now we can proceed with next step.

Step 2: Deleting the unwanted partition

We can delete the unwanted partitions using the Disk Management utility itself. Be careful to do these operations, as once deleted, the data inside that partition will not be recoverable. If you are not sure about the data inside the Pen drive, then you may try to back up your Pen Drive before attempting this. Moreover, deleting the wrong partition (In the Hard disk) will result that your PC will also stop working and data will be lost.

After selecting the Pen Drive partition carefully, right click on the partition you want to delete. It will show the option “Delete” and click on that. Be sure that you are working on the Pen Drive partition. It will ask for a confirmation about the data loss. Once we are accepting it, the unwanted partition will get deleted. After deletion, the unallocated space will get increased to the tune of Pen Drive Capacity.

recover pen drive lost space

If the Pen Drive is not yet formatted in any Windows PC yet, now you can go to the Step 4: Formatting by skipping the next Step. If you already formatted the device in Windows and it shows the reduced capacity, then we need to perform the Step 3 to expand the storage capacity.

Step 3: Recovering the lost partition using Diskpart utility

The Pen Drive partition once formatted, will not allow us to expand the partition as like in the normal Disk Drive. To restore the capacity, we need to delete the small partition that was created during the formatting of the Drive in Windows PC. We can use the Diskpart utility available in Windows. Open Command Prompt and type Diskpart to open this utility. It will ask for the Administrator Privilage Confirmation and will open a separate window with DISKPART> prompt similar to command prompt.  Now type “List Disk” to know how many disks are connected. Normally, Disk 0 will be the Hard disk that we need to avoid from these operations. If no other disks are there, it will show Disk 1 as Pen Drive.

DISKPART> list disk

  Disk ###  Status         Size     Free     Dyn  Gpt
——–  ————-  ——-  ——-  —  —
Disk 0    Online          931 GB      0 B
Disk 1    Online           14 GB      0 B

Verify that and type “Select Disk 1” to select that drive.

DISKPART> select disk 1

Disk 1 is now the selected disk.

Now type “List Partition” to see the available partitions in the selected disk. Verify that you are working on Pen Drive by checking the List partition results with the Pen Drive available space.

DISKPART> list partition

  Partition ###  Type              Size     Offset
————-  —————-  ——-  ——-
Partition 1    Primary            295 MB    16 KB

Once verified, type “Select Partition 1” to do further operation.

DISKPART> select partition 1

Partition 1 is now the selected partition.

Once you are verified that you working on Pen Drive partition, Type “Delete Partition” to delete the selected partition fully. Be aware that there won’t be any prompts here and once deleted, all data will be lost. The Diskpart utility will perform the operations in the selected partition only so that it will not affect other partitions. You can confirm the selected partition by typing the “detail partition” command.

DISKPART> detail partition

Partition 1
Type  : 06
Hidden: No
Active: No
Offset in Bytes: 16384

  Volume ###  Ltr  Label        Fs     Type        Size     Status     Info
———-  —  ———–  —–  ———-  ——-  ———  ——–
* Volume 4     E                FAT    Removable    295 MB  Healthy

DISKPART> delete partition

DiskPart successfully deleted the selected partition.

Once you have deleted the partition, the process is almost over. The Pen Drive Capacity will be restored fully now. To utilize this capacity we need to format the Pen Drive finally.

Step 4: Formatting

We may eject the Pen Drive and re insert again. Now the Windows will ask for to format the device. You can also use other familiar options to format the Pen Drive. Now we can format the device as per our choice. We can confirm from the format window itself about the available space in the Pen Drive and it will show the full capacity there. Now we have fully recovered the lost Pen Drive space without installing any third party Applications.

recover pen drive lost space

In addition to this, there are utilities available from the manufacturers web sites for repairing the Pen Drives. If you are not able to proceed in between any of the steps, you may check those utilities available from the manufacturers only.

Related: How to Connect External Hard Disk to Home Network over WiFi without PC

Most of the Pen Drives are coming with Life Time warranty so that those drives which are not getting detected or not able to access may be replaced by manufacturers once we are raising the complaints with them.


  1. DISKPART> detail partition

    Partition 1
    Type : 0C
    Hidden: No
    Active: No
    Offset in Bytes: 16384

    Volume ### Ltr Label Fs Type Size Status Info
    ———- — ———– —– ———- ——- ——— ——–
    * Volume 5 I ABHI FAT32 Removable 14 GB Healthy

    DISKPART> delete partition

    DiskPart has encountered an error: The request could not be performed because of an I/O device error.
    See the System Event Log for more information.

    Type is 0C means what and delete partition showing error please help

Leave a comment