A 961 KB RAR archive associated with MSI motherboard MS-7166. Only the board number is given, so whether the content is firmware or documentation must be checked after unpacking. The small size could suit a BIOS image, but that is not confirmed by the name. MS-7xxx is MSI's desktop board numbering, printed on the PCB. Match it and the revision, compare any image size with the flash chip capacity, and dump the original chip before writing a replacement 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.
7-ZipWinRARThe Unarchiver (macOS)