Archive named only after the Compal board number LA-5251P, with no laptop brand, model or revision stated. Compal uses the LA-xxxxP pattern for its notebook mainboards, which ship under several brands, so the buyer's model must be matched through the code printed on the PCB. The 1.50 MB RAR is probably a schematic, possibly with a boardview, but the contents are unconfirmed. Extract it with WinRAR or 7-Zip and use it to trace rails, locate parts and diagnose no-power faults after checking the revision.
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 @IT_SERVICE_WORLD. 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.