diff --git a/Makefile.libcoap b/Makefile.libcoap
index 09275aae..1035c64b 100644
--- a/Makefile.libcoap
+++ b/Makefile.libcoap
@@ -1,4 +1,4 @@
-libcoap_src = pdu.c net.c coap_debug.c encode.c uri.c subscribe.c resource.c str.c option.c async.c block.c mem.c coap_io.c coap_session.c coap_notls.c coap_hashkey.c address.c
+libcoap_src = pdu.c net.c coap_debug.c encode.c uri.c subscribe.c resource.c str.c option.c async.c block.c mem.c coap_io.c coap_session.c coap_notls.c coap_hashkey.c address.c coap_tcp.c
 
 libcoap_dir := $(filter %libcoap,$(APPDS))
 vpath %c $(libcoap_dir)/src
diff --git a/examples/client.c b/examples/client.c
index 2ce48de5..794148f5 100644
--- a/examples/client.c
+++ b/examples/client.c
@@ -829,6 +829,13 @@ cmdline_uri(char *arg, int create_uri_opts) {
       return -1;
     }
 
+    if (uri.scheme==COAP_URI_SCHEME_COAP_TCP && !coap_tcp_is_supported()) {
+      /* coaps+tcp caught above */
+      coap_log(LOG_EMERG,
+            "coap+tcp URI scheme not supported in this version of libcoap\n");
+      return -1;
+    }
+
     if (uri.port != get_default_port(&uri) && create_uri_opts) {
       coap_insert_optlist(&optlist,
                   coap_new_optlist(COAP_OPTION_URI_PORT,
diff --git a/examples/lwip/Makefile b/examples/lwip/Makefile
index 1e9073c7..819dd54f 100644
--- a/examples/lwip/Makefile
+++ b/examples/lwip/Makefile
@@ -39,7 +39,7 @@ CFLAGS += -I$(top_srcdir)/include/coap2
 
 vpath %.c $(top_srcdir)/src
 
-COAPOBJS = net.o coap_debug.o option.o resource.o pdu.o encode.o subscribe.o coap_io_lwip.o block.o uri.o str.o coap_session.o coap_notls.o coap_hashkey.o address.o
+COAPOBJS = net.o coap_debug.o option.o resource.o pdu.o encode.o subscribe.o coap_io_lwip.o block.o uri.o str.o coap_session.o coap_notls.o coap_hashkey.o address.o coap_tcp.o
 
 CFLAGS += -g3 -Wall -Wextra -pedantic -O0 -fpack-struct
 # not sorted out yet
diff --git a/src/coap_session.c b/src/coap_session.c
index b5873a6c..1d05d625 100644
--- a/src/coap_session.c
+++ b/src/coap_session.c
@@ -658,8 +658,33 @@ coap_session_create_client(
   coap_session_t *session = NULL;
 
   assert(server);
-  assert(proto != COAP_PROTO_NONE);
 
+  switch(proto) {
+  case COAP_PROTO_UDP:
+    break;
+  case COAP_PROTO_DTLS:
+    if (!coap_dtls_is_supported()) {
+      coap_log(LOG_CRIT, "coap_new_client_session*: DTLS not supported\n");
+      return NULL;
+    }
+    break;
+  case COAP_PROTO_TCP:
+    if (!coap_tcp_is_supported()) {
+      coap_log(LOG_CRIT, "coap_new_client_session*: TCP not supported\n");
+      return NULL;
+    }
+    break;
+  case COAP_PROTO_TLS:
+    if (!coap_tls_is_supported()) {
+      coap_log(LOG_CRIT, "coap_new_client_session*: TLS not supported\n");
+      return NULL;
+    }
+    break;
+  case COAP_PROTO_NONE:
+  default:
+    assert(0);
+    break;
+  }
   session = coap_make_session(proto, COAP_SESSION_TYPE_CLIENT, local_if,
     local_if, server, 0, ctx, NULL);
   if (!session)
@@ -1024,12 +1049,15 @@ coap_new_endpoint(coap_context_t *context, const coap_address_t *listen_addr, co
     goto error;
   }
 
-#if !COAP_DISABLE_TCP
   if (proto == COAP_PROTO_TLS && !coap_tls_is_supported()) {
     coap_log(LOG_CRIT, "coap_new_endpoint: TLS not supported\n");
     goto error;
   }
-#endif /* !COAP_DISABLE_TCP */
+
+  if (proto == COAP_PROTO_TCP && !coap_tcp_is_supported()) {
+    coap_log(LOG_CRIT, "coap_new_endpoint: TCP not supported\n");
+    goto error;
+  }
 
   if (proto == COAP_PROTO_DTLS || proto == COAP_PROTO_TLS) {
     if (!coap_dtls_context_check_keys_enabled(context)) {
diff --git a/src/uri.c b/src/uri.c
index 2107ce95..67ab8603 100644
--- a/src/uri.c
+++ b/src/uri.c
@@ -79,7 +79,6 @@ coap_split_uri(const uint8_t *str_var, size_t len, coap_uri_t *uri) {
   }
 
   /* There might be and addition "+tcp", indicating reliable transport: */
-#if !COAP_DISABLE_TCP
   if (len>=4 && p[0] == '+' && p[1] == 't' && p[2] == 'c' && p[3] == 'p' ) {
     p += 4;
     len -= 4;
@@ -88,7 +87,6 @@ coap_split_uri(const uint8_t *str_var, size_t len, coap_uri_t *uri) {
     else
       uri->scheme = COAP_URI_SCHEME_COAP_TCP;
   }
-#endif /* !COAP_DISABLE_TCP */
   q = (const uint8_t *)"://";
   while (len && *q && *p == *q) {
     ++p; ++q; --len;