You likely need a headerless version of the game file that is required. This tool can remove the header for you.
The following is the known valid CRC code for the required game file.
C50A8304: Contra (NES)
ROM info for the file you provided:
- Filename: {{file.name}}
- Headered: {{isHeadered | yesno}}
- CRC32: {{crc | upper}} (headerless: {{calcCrcHeaderless | upper}})
- Filesize: {{file.size}} bytes ({{parseInt(file.size/1024)}} kbytes, {{parseInt(file.size/1024/1024)}} mbytes)
- {{genError()}}
- This seems to match.
- The file you selected looks like it could be a compressed file.
- If it's a
.zip, your operating system should be able to extract it by right-clicking.
- If it's a
.7z, you'll need 7-Zip (which is primarily a Windows application) to extract it.
- If it's a
.rar, you'll need WinRAR (which is primarily a Windows application) to extract it.