| 31. | .config | application/x-ns-proxy-autoconfig |
| 32. | .cpio | application/x-cpio |
| 33. | .cpp | text/x-c |
| 34. | .cpt | application/mac-compactpro ◊ application/x-compactpro ◊ application/x-cpt |
| 35. | .crd | application/x-mscardfile |
| 36. | .crl | application/pkix-crl ◊ application/pkcs-crl |
| 37. | .crt | application/pkix-cert ◊ application/x-x509-ca-cert ◊ application/x-x509-user-cert |
| 38. | .csh | application/x-csh ◊ text/x-script.csh |
| 39. | .csm | chemical/x-csml |
| 40. | .csml | chemical/x-csml |