RAR file of 1.32 MB for the ECS H61H-AIO board, revision 1.0. The name references an Intel H61 chipset and, by its AIO suffix, an all-in-one system board, though which PCs used it is not stated. Contents are unlisted and are probably a schematic, useful for tracing the DC input and VRM rails, panel and backlight power, and the signals that hold the system in standby. Open it with WinRAR or 7-Zip and compare the board marking and revision before relying on the drawings for repair.
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.