Material for the HP ProBook 450 G7 mainboard DA0X8MMB6D0, revision D, packed as an 8.73 MB RAR archive. Board numbers starting with DA0 follow the Quanta pattern, where the letters in the middle name the project and the end shows the PCB revision. Typical content is a schematic or boardview used to find shorted capacitors, check power-on sequence signals and identify parts. Make sure the revision on your board is also D, as other revisions may differ.
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 @ShareMan_Electronic_Files. 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.
7-ZipWinRARThe Unarchiver (macOS)