Windows executable named Winflash, a utility for updating BIOS firmware from within Windows. The name does not say which manufacturer or model it targets, and several vendors, ASUS among them, have shipped tools with this name. Software like this flashes a board that still boots, while a dead board needs an external SPI programmer instead. Run it only with a BIOS file meant for the exact model, keep the machine on stable power during the update, and scan the file before running it.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @technodev_bios. Enginerys does not host this file.