diff --git a/acarsdec.c b/acarsdec.c
index 4c16972..275db05 100644
--- a/acarsdec.c
+++ b/acarsdec.c
@@ -580,7 +580,7 @@ char * parse_params(char **paramsp, struct params_s *sp, const int np)
 	while ((param = strsep(paramsp, ","))) {
 		sep = strchr(param, '=');
 		if (!sep)
-			continue;
+			return param;
 
 		*sep++ = '\0';
 
diff --git a/fileout.c b/fileout.c
index ed7201b..fe94853 100644
--- a/fileout.c
+++ b/fileout.c
@@ -87,7 +87,7 @@ fileout_t *Fileoutinit(char *params)
 
 	retp = parse_params(&params, filep, ARRAY_SIZE(filep));
 	if (retp) {
-		fprintf(stderr, ERRPFX "unknown parameter '%s'\n", retp);
+		fprintf(stderr, ERRPFX "invalid parameter '%s'\n", retp);
 		return NULL;
 	}
 
diff --git a/mqttout.c b/mqttout.c
index a3f7560..bcdc2cf 100644
--- a/mqttout.c
+++ b/mqttout.c
@@ -50,7 +50,9 @@ mqttout_t *MQTTinit(char *params)
 	do {
 		retp = parse_params(&params, mqttp, ARRAY_SIZE(mqttp));
 		if (retp) {
-			sep = strchr(retp, '=');	// guaranteed to exist due to parse_params()
+			sep = strchr(retp, '=');
+			if (!sep)
+				goto unknown;
 			*sep++ = '\0';
 			if (!strcmp("uri", retp)) {
 				if (url > &urls[14])
@@ -59,7 +61,8 @@ mqttout_t *MQTTinit(char *params)
 					*url++ = sep;
 			}
 			else {
-				fprintf(stderr, ERRPFX "unknown parameter '%s'\n", retp);
+unknown:
+				fprintf(stderr, ERRPFX "invalid parameter '%s'\n", retp);
 				return NULL;
 
 			}
diff --git a/netout.c b/netout.c
index 26ae380..fccafef 100644
--- a/netout.c
+++ b/netout.c
@@ -51,7 +51,7 @@ netout_t *Netoutinit(char *params)
 
 	retp = parse_params(&params, netp, ARRAY_SIZE(netp));
 	if (retp) {
-		fprintf(stderr, ERRPFX "unknown parameter '%s'\n", retp);
+		fprintf(stderr, ERRPFX "invalid parameter '%s'\n", retp);
 		return NULL;
 	}
 
diff --git a/statsd.c b/statsd.c
index 49202e2..c1a3fd0 100644
--- a/statsd.c
+++ b/statsd.c
@@ -61,7 +61,7 @@ int statsd_init(char *params, const char *idstation)
 
 	retp = parse_params(&params, statsdp, ARRAY_SIZE(statsdp));
 	if (retp) {
-		fprintf(stderr, ERRPFX "unknown parameter '%s'\n", retp);
+		fprintf(stderr, ERRPFX "invalid parameter '%s'\n", retp);
 		return -1;
 	}