If the receiver won't turn on (boot loop), you may need an RS232 cable and "loader" software on a PC to force-flash the dump file. Where to find it
Use a tool like 7-Zip or WinRAR to extract the .bin file inside the ZIP archive. Download Dump 1515HD PRIME zip
Place the .bin file on a FAT32-formatted USB drive, plug it into the receiver, and use the "Software Update" menu. If the receiver won't turn on (boot loop),