RAR archive of 4.71 MB tied to the MSI MS-7191 board. The name gives no hint of the contents, so it may hold a schematic, a BIOS image or other service material; open it with WinRAR or 7-Zip to find out. MSI numbers its desktop motherboards in the MS-7xxx series, and the number is silkscreened on the PCB, usually between the slots. Confirm that number and the board revision before using anything inside, and save the original BIOS chip contents with a programmer before writing a new image.
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 @IT_SERVICE_WORLD. Enginerys does not host this file.
How to open a .rar file
Compressed archive — the usual wrapper for a schematic + boardview pair or a BIOS + EC set.