diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7fe6185b..95c36f5d 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -425,8 +425,7 @@ auto_test(send_message)
 auto_test(set_name)
 auto_test(set_status_message)
 auto_test(skeleton)
-# TODO(iphydf): Fix this test and re-enable.
-#auto_test(tcp_relay)
+auto_test(tcp_relay)
 auto_test(tox_many)
 auto_test(tox_many_tcp)
 auto_test(tox_one)
diff --git a/auto_tests/tcp_relay_test.c b/auto_tests/tcp_relay_test.c
index b9eea92d..fcb1fdef 100644
--- a/auto_tests/tcp_relay_test.c
+++ b/auto_tests/tcp_relay_test.c
@@ -24,7 +24,12 @@ int main(void)
     tox_options_free(opts);
 
     tox_bootstrap(tox_tcp, "tox.initramfs.io", 33445, key, nullptr);
-    tox_add_tcp_relay(tox_tcp, "tox.initramfs.io", 33445, key, nullptr);
+
+    Tox_Err_Bootstrap tcp_err;
+    tox_add_tcp_relay(tox_tcp, "tox.initramfs.io", 33445, key, &tcp_err);
+    ck_assert_msg(tcp_err == TOX_ERR_BOOTSTRAP_OK,
+                  "attempting to add tcp relay returned with an error: %d",
+                  tcp_err);
 
     printf("Waiting for connection");
 
diff --git a/toxcore/network.c b/toxcore/network.c
index 3f297ad7..e5a58331 100644
--- a/toxcore/network.c
+++ b/toxcore/network.c
@@ -956,6 +956,10 @@ Networking_Core *new_networking_ex(const Logger *log, IP ip, uint16_t port_from,
 
 Networking_Core *new_networking_no_udp(const Logger *log)
 {
+    if (networking_at_startup() != 0) {
+        return nullptr;
+    }
+
     /* this is the easiest way to completely disable UDP without changing too much code. */
     Networking_Core *net = (Networking_Core *)calloc(1, sizeof(Networking_Core));