HP ProBook 4540s archive, 416 KB, with no document type stated in the name. At this size it most likely contains a BIOS or EC firmware dump rather than a schematic. Technicians use such dumps to recover boards with corrupted firmware by writing the SPI flash with a programmer. Open it with WinRAR or 7-Zip, verify the image matches the flash chip capacity, and confirm the board number printed on the PCB; read and save the original chip before writing to preserve serial and licence data.
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 @hrtechno. 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.