Service archive for the MSI MS-7138 board, 2.08 MB, RAR compressed. The name carries only the brand and board code, with no revision or content type, so check what is included after unpacking. MSI uses the MS-7xxx designation for desktop motherboards and prints it near the slots along with a revision. A schematic in the package helps when measuring rails and signals, while a BIOS image can repair corrupted firmware. Save the original chip contents before flashing.
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.