An archive of repair files for Acer hardware (board LA-6552P). Shared as “Acer_Aspire_5552_COMPAL_LA_6552P.rar” — a .rar file, 1.85 MB.
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 @alischematics. 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.