RAR archive holding the ASUS repair guide for the Z170-P desktop motherboard, an Intel Z170 chipset board for Skylake processors. ASUS service repair guides typically walk through power-on sequence, key voltage rails, test points and common failure symptoms with board photos marking where to measure. Use it alongside a multimeter when diagnosing no-power or no-POST faults. At 2.44 MB it is likely PDF pages or images; extract with WinRAR or 7-Zip and confirm the board model and revision silkscreened on the PCB match.
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 @ZINFOSERVICECHANNEL1. 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.