MSI MS-7038 files compressed as a 1.90 MB RAR. The name is bare, stating neither revision nor contents, so unpack it with 7-Zip or WinRAR and see what it holds. MS-7xxx codes are MSI's in-house desktop motherboard numbers, printed on the PCB with a revision marking. Match both before use. A schematic supports rail tracing and fault finding around the VRM and chipset; a BIOS dump can restore a board that fails to post, once the original flash has been read and saved.
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.