Even a stable tool can encounter problems. Here are solutions to frequent user complaints.
Create a folder named ULE_V412 on your PC. Inside, create a subfolder BOOT. Place your renamed BOOT.ELF (uLaunchELF V4.12) inside BOOT. If you want extra apps, create another folder named APPS and place them there (e.g., HDLOADER.ELF).
The primary purpose of uLaunchELF is file management. The PS2 natively hides its system files and makes transferring data difficult. uLaunchELF smashes that wall down.
The uLaunchELF project has seen dozens of releases, from v3.41 to v4.47a (the final official build). So why is Version 4.12 still so frequently searched and discussed?