Selecting The Correct File System


Your device is formatted as NTFS from the factory. The Sentry K300 can be reformatted to any file system of your choosing to accommodate a different operating system or to remove file size restrictions.


Recommended file systems:

  • FAT32
    • Pros: Cross-platform compatible (Windows, macOS, and Linux)
    • Cons: Limited individual file size of 4GB
  • NTFS
    • Pros: No file size limitations
    • Cons: Limited cross-platform compatibility - Windows, macOS (read-only), and Linux (read-only)
  • exFAT
    • Pros: No file size limitations
    • Cons: Not supported by legacy operating systems


Note: Reformatting your Sentry K300 drive will erase all your files but will not erase your device password and settings. This should not be used as a method of securely erasing files. To securely erase your files, perform a Zeroize function.


Important: Before you reformat the device, back up your drive to a separate location, for example, to cloud storage or your computer.


Formatting On Windows

  1. Unlock your device using the administrator password.
  2. Connect the device to your Windows computer.
  3. Download the DataLocker Disk Formatter Tool: https://media.datalocker.com/downloads/tools/Datalocker_Disk_Formatter_v2.0.11.exe
  4. Run the DataLocker_Disk_Formatter.exe. The formatting tool will automatically find the Sentry K300 device.
  5. Select the Drive Letter and Format Type, and rename your Drive Label.

  6. Click Start Format.

  7. The formatting tool will show Formatting drive...
    Note: Windows may recognize that the drive needs to be formatted after the formatting tool has already started. Feel free to close any popups from Windows that say the drive needs to be formatted.

  8. When finished, the formatting tool should display the message “The formatting has successfully finished!

  9. Your Sentry K300 will now appear under This PC.


Formatting On macOS

  1. Unlock your device using the administrator password.
  2. Connect the device to your macOS computer.
  3. Go to Applications under Finder.
  4. Click on Utilities, then double click Disk Utility.
  5. Select the Sentry K300 disk.
  6. Click the Erase tab.
  7. Choose the new file system from the dropdown and rename your disk label.
  8. Click Erase.
    Your Sentry K300 will now appear under Devices.


Formatting On Linux
The Sentry K300 is platform independent, capable of being run with 100% compatibility on most systems. For optimal Linux or Unix based system compatibility, we recommend using at least the Linux 2.6.31 Kernel (released 9 September 2009), which implemented the xHCI specification for USB 3.0. Although older versions should work, they might run in USB 2.0 mode, which can be significantly slower.


In most newer distributions the drive should automatically mount. To format the drive, first enter terminal, then list detected hard disks using


        # fdisk -l | grep '^Disk'


Your configuration may vary. For this example, we’ll assume the disk is at /dev/sdb


You will then type:


        # fdisk /dev/sdb


Follow the instructions in fdisk to create a new partition.


Finally you’ll use the mkfs command to format the disk for Linux. Here, we use ext4.


        # mkfs.ext4 /dev/sdb1


If you want to rename the drive, use the e2label command.


        # e2label /dev/sdb1 /DataLocker