RAR archive of 2.40 MB titled C90S, apparently for the ASUS C90S notebook, though the name carries no board number, revision or content type. Unpack it with 7-Zip or WinRAR to check whether it includes a schematic, boardview data or firmware. Schematic material is useful for tracing power rails, identifying the circuitry around a failing part and checking a suspected short. Before using any of it, compare the board number and revision printed on the PCB with those shown in the documentation.
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.