Compressed service file for the MSI MS-7143, an 800 KB RAR package. The file name gives no detail about revision or content type, so treat it as a general resource for this board until you have checked it. Unpack it with WinRAR or 7-Zip. A BIOS image can be written with an SPI programmer or a flashing tool, and a schematic is useful for checking voltage regulators and signal paths. Make sure the MS-7143 number and revision on the board match, and keep a backup of the original firmware.
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.