Windows says “You need to format the disk before you can use it,” but formatting fails.

Click Create . The software will process the file and generate several numbered segments (e.g., ul.01 , ul.02 ) along with a configuration file.

Run a disk defragmentation tool (such as Defraggler) on your USB drive after transferring games. Alternatively, check the OPL compatibility list to see if the game requires specific "Mode" settings enabled on the console.

This is usually caused by game fragmentation on the USB drive. Because FAT32 writes data in chunks, files easily become fragmented, which the weak PS2 USB 1.1 ports struggle to read. Download a free PC defragmentation tool (like Auslogics Disk Defrag or Defraggler) and run it strictly on your USB drive. 2. "Error in ISO" or "Bad Structure" Message

Disclaimer: Ensure you only use this tool to create backups of games you personally own. How to Use USBUtil V2.00 (Step-by-Step)