Archive in RAR format, 1.17 MB, for the Toshiba Satellite L850 on a Pegatron-made motherboard, as the name states. No board number or revision is given, so compare the Pegatron code on the PCB with the documents once unpacked. Such files are typically schematics or boardviews used to trace power rails, check signals at connectors, locate components and test points, and narrow down a short. L850 units also came on other ODM boards, so the match matters.
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.
7-ZipWinRARThe Unarchiver (macOS)