diff --git a/source3/utils/nmblookup.c b/source3/utils/nmblookup.c
index 86902941746..a78967fdb88 100644
--- a/source3/utils/nmblookup.c
+++ b/source3/utils/nmblookup.c
@@ -389,6 +389,11 @@ int main(int argc, const char *argv[])
 		case 'T':
 			translate_addresses = !translate_addresses;
 			break;
+		case POPT_ERROR_BADOPT:
+			fprintf(stderr, "\nInvalid option %s: %s\n\n",
+				poptBadOption(pc, 0), poptStrerror(opt));
+			poptPrintUsage(pc, stderr, 0);
+			exit(1);
 		}
 	}