A repair software package. Shared as “Micromax L50 Yuphoria_Software (TP.MT5510.PC821).rar” — a .rar file, 738 MB.
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 @hashmielecom. 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)