RAR archive of roughly 879 KB labelled only with the board code IPISB-NK, which is a Pegatron mainboard found in some HP all-in-one desktops. The name gives no revision, model or content type, so the archive could contain service documentation or firmware and should be inspected before use. Material for this board is typically used to trace power sequencing, check standby rails and locate parts during repair. Compare the board marking and revision on the actual PCB with whatever the archive contains before relying on it.
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.