diff --git a/src/config2setopts.c b/src/config2setopts.c
index 459b7caa95..4d62e67106 100644
--- a/src/config2setopts.c
+++ b/src/config2setopts.c
@@ -950,7 +950,7 @@ static CURLcode credentials_and_headers_setopts(struct OperationConfig *config,
 
   result = my_setopt_slist(curl, CURLOPT_HTTPHEADER, config->headers);
   if(result) {
-    errorf("Illegal content in --header data");
+    errorf("Illegal CRL/LF in --header data");
     config->synthetic_error = TRUE;
     return result;
   }