ZIP archive of 951 KB for the Sony motherboard MBX-224; the name does not list what is inside, so it may hold a schematic, boardview or other service data. Sony marks its laptop boards with MBX numbers, while the actual design usually comes from an ODM such as Quanta or Foxconn. Extract it with any archive tool and check the contents before use. Whatever the files are, confirm the MBX code on the PCB matches 224 so rails, parts and pinouts correspond to the board on the bench.
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 @cyberlanelectonik. Enginerys does not host this file.
How to open a .zip file
Compressed archive that every operating system opens without extra software.