Small 99.8 KB RAR archive named only QT6B, with no brand or file type given. QT6 is likely a project code, but the name does not say whether it holds a boardview, schematic or firmware, so extract it and identify the contents before use. The modest size fits a boardview or small firmware file better than a full schematic set. Whatever it contains, compare the code and revision printed on the motherboard with the files inside before using it for diagnosis or flashing.
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 @schematicslaptop. 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.