Compressed RAR package of 956 KB for the MSI MS-7031 motherboard, following MSI's own MS-xxxx numbering, where 7xxx codes generally denote desktop boards. No revision is given in the name, so the contents, most plausibly a schematic, should be checked against the revision printed near the board number on the PCB. A circuit diagram like this helps a repair technician follow VRM and standby rails, locate fuses and MOSFETs, and work out where a short to ground originates before replacing parts.
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.