RAR package for the N5010 platform in its Intel version, a model designation used for Dell Inspiron notebooks although no brand is given in the name. Around 1018 KB, it most likely contains the motherboard schematic or a boardview file. The board revision is not listed, so check the number printed on the PCB before trusting component references, measuring rails or chasing a short. Unpack it with 7-Zip or WinRAR, then open PDF drawings in a viewer or boardview files in a tool such as OpenBoardView.
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.