RAR archive, 791 KB, for the Quanta ZHY mainboard, revision 3A. The name gives no laptop brand or model, so identify the notebook by the code and board number on the PCB. Quanta manufactures boards for several brands under such project codes, and the matching board number normally begins with DA0ZHY. A schematic from a package like this is used for tracing rails, checking for shorts and locating test points around the power circuits. Confirm the revision is 3A before relying on the document.
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.