Firmware build V3758 for the StarTrack SRT-550 HD Platinum satellite receiver, dated 20170711, in a 2.78 MB RAR archive. It is an earlier release than V4101 and useful when a later version causes problems or a known-good older build is needed. Flash it through the receiver's upgrade function or over RS232 when the box no longer boots. Verify the model and main board before writing, and dump the existing flash so the previous state can be restored if necessary.
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 @tvsoftwareworld. 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)