Download the official version from the MSFN Forums or MajorGeeks. Happy reducing.
Here are some tips and tricks to help you get the most out of WinReducer EX-80: WinReducer EX-80
He flashed it to a USB drive. He plugged it into his old Dell XPS. The BIOS screamed—unsigned bootloader, missing certificates, temporal security violation. But the WinReducer had left one last gift: a tiny, embedded EFI shim that whispered "Legacy mode engaged" to the motherboard. Download the official version from the MSFN Forums