: Many ROM hacks and translation patches are designed for "raw" (headerless) files. If you apply them to an .smc file, the data will be offset by 512 bytes, causing the game to crash or display a black screen. Database Matching
: If the file already lacks a header (and just uses the .smc extension), you can simply rename the extension to .sfc. If a header exists, however, renaming won't remove the extra data. smc to sfc converter