ECS TIGD-CI3 Mini-ITX motherboard documentation, revision 1.1, packed as an 862 KB RAR. The Mini-ITX form factor is stated in the name, which helps confirm the board type. The archive most likely holds the schematic, useful for tracing power rails, locating the SuperIO and BIOS chip and diagnosing boards that do not start. Extract with WinRAR or 7-Zip, then check that the model and revision 1.1 printed on the PCB match before measuring or replacing components based on these drawings.
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.