Instead of searching for a serial key for an outdated version like 2.5.4, you should download the . It is faster, handles XL (Extra Large) drives for the original Xbox (up to 16TB), and features a much cleaner user interface. How to Get FatXplorer Legally
FATXplorer 2.5.4 is a specialized Windows-based utility designed to manage Xbox 360 storage devices, such as hard drives and USB sticks. To fully utilize its professional-grade features, users require a valid or license key obtained through the developer. Licensing Options for FATXplorer