Prompted to format when double-clicking the drive letter.

Applicable Models

D5-300

The partition file system may be corrupted. (For large-capacity disks, the exFAT format is not recommended. On Windows, NTFS is recommended; on macOS, APFS is recommended.)
Please try to repair the file system.
Windows method:

1. Click "Start", open "Run", type "cmd" and press Enter to launch the Command Prompt.
2. In the Command Prompt, type "chkdsk H: /f" and press Enter to execute (H: should be replaced with the drive letter of the faulty disk). macOS method:
   Open "Disk Utility", select the USB volume on the left.
   Click "First Aid" at the top and perform the repair.
   After the repair is complete, try manually "Mount".