diff --git a/source/CMakeLists.txt b/source/CMakeLists.txt
index 13840d1..e4e1133 100644
--- a/source/CMakeLists.txt
+++ b/source/CMakeLists.txt
@@ -10,7 +10,10 @@ add_definitions(${GTK_CFLAGS_OTHER})
 find_package(ICU REQUIRED COMPONENTS uc dt in io)
 
 #set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -pedantic -Wall -Wextra -Werror -Wmissing-declarations -fdiagnostics-color=always -std=c++2a")
-set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -pedantic -Wall -Wextra -Werror -Wmissing-declarations -fdiagnostics-color=always")
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -pedantic -Wall -Wextra -Werror -Wmissing-declarations -fdiagnostics-color=always \
+	-O2 -pipe -fno-plt -fexceptions \
+        -Wp,-D_FORTIFY_SOURCE=2 -Wformat -Werror=format-security \
+        -fstack-clash-protection -fcf-protection")
 
 set(SOURCE_FILES
         main.cc 
diff --git a/source/ubl-settings-datetime.cc b/source/ubl-settings-datetime.cc
index 0dc4cdd..6638135 100644
--- a/source/ubl-settings-datetime.cc
+++ b/source/ubl-settings-datetime.cc
@@ -288,25 +288,25 @@ void MainWindow::wind_close_ntp(){
 
 void MainWindow::stop_ntp(){
     string cmd = "SEL_SERVICE=\"systemd-timesyncd\"; systemctl --quiet is-active ${SEL_SERVICE}.service &>/dev/null && systemctl stop ${SEL_SERVICE}.service; ";
-    system(cmd.c_str());
+    response_cmd=system(cmd.c_str());
     cmd ="SEL_SERVICE=\"ntpd\"; systemctl --quiet is-active ${SEL_SERVICE}.service &>/dev/null && systemctl stop ${SEL_SERVICE}.service || pkill -9 ${SEL_SERVICE}; ";
-    system(cmd.c_str());
+    response_cmd=system(cmd.c_str());
     cmd ="SEL_SERVICE=\"ntpdate\"; systemctl --quiet is-active ${SEL_SERVICE}.service &>/dev/null && systemctl stop ${SEL_SERVICE}.service || pkill -9 ${SEL_SERVICE}; ";
-    system(cmd.c_str());
+    response_cmd=system(cmd.c_str());
     cmd = "SEL_SERVICE=\"chronyd\"; systemctl --quiet is-active ${SEL_SERVICE}.service &>/dev/null && systemctl stop ${SEL_SERVICE}.service || pkill -9 ${SEL_SERVICE}; ";
-    system(cmd.c_str());
+    response_cmd=system(cmd.c_str());
     cmd ="SEL_SERVICE=\"openntpd\"; systemctl --quiet is-active ${SEL_SERVICE}.service &>/dev/null && systemctl stop ${SEL_SERVICE}.service || pkill -9 ntpd; ";
-    system(cmd.c_str());
+    response_cmd=system(cmd.c_str());
     cmd ="SEL_SERVICE=\"ptp4l\"; systemctl --quiet is-active ${SEL_SERVICE}.service &>/dev/null && systemctl stop ${SEL_SERVICE}.service || pkill -9 ${SEL_SERVICE}; ";
-    system(cmd.c_str());
+    response_cmd=system(cmd.c_str());
     cmd ="SEL_SERVICE=\"phc2sys\"; systemctl --quiet is-active ${SEL_SERVICE}.service &>/dev/null && systemctl stop ${SEL_SERVICE}.service || pkill -9 ${SEL_SERVICE} ";
-    system(cmd.c_str());
+    response_cmd=system(cmd.c_str());
 
 }
 
 void MainWindow::hardware_clock(){
     string cmd = "hwclock --systohc";
-    system(cmd.c_str());
+    response_cmd=system(cmd.c_str());
 }
 
 void MainWindow::gui_mess_close(){
@@ -354,7 +354,7 @@ void MainWindow::event_entry_cbDhcp(){
         if (activ_index==0){
             btnUpdateDateTime->set_sensitive(false);
             string cmd = "/usr/bin/ubconfig set network NTPSERVERS=default";
-            system(cmd.c_str());
+            response_cmd=system(cmd.c_str());
             txtNtpServer->set_sensitive(false);
             cbDhcp->set_active(activ_index);
             string response = this->call("/usr/bin/ubconfig --source=default get NTPSERVERS_DEFAULT");
@@ -364,7 +364,7 @@ void MainWindow::event_entry_cbDhcp(){
         else if (activ_index==1){
             btnUpdateDateTime->set_sensitive(false);
             string cmd = "/usr/bin/ubconfig set network NTPSERVERS=dhcp";
-            system(cmd.c_str());
+            response_cmd=system(cmd.c_str());
             txtNtpServer->set_sensitive(false);
             cbDhcp->set_active(activ_index);
             txtNtpServer->set_text("");
@@ -387,7 +387,7 @@ void MainWindow::event_entry_cbDhcp(){
         }
         else if (activ_index==3){
             string cmd = "/usr/bin/ubconfig remove network NTPSERVERS";
-            system(cmd.c_str());
+            response_cmd=system(cmd.c_str());
             txtNtpServer->set_text("");
             txtNtpServer->set_sensitive(false);
             btnUpdateDateTime->set_sensitive(true);
@@ -397,7 +397,7 @@ void MainWindow::event_entry_cbDhcp(){
         
     else{
         string cmd = "/usr/bin/ubconfig set network NTPSERVERS=dhcp";
-        system(cmd.c_str());
+        response_cmd=system(cmd.c_str());
         cbDhcp->set_active(0);
     }
 }
@@ -465,7 +465,9 @@ void MainWindow::enry_dhcp_mess(){
         else if (str_dhcp=="default"){
             btnUpdateDateTime->set_sensitive(false);
             cbDhcp->set_active(0);
-            txtNtpServer->set_text("");
+            string response = this->call("/usr/bin/ubconfig --source=default get NTPSERVERS_DEFAULT");
+            this->str_remove(response, "\n");
+            txtNtpServer->set_text(response);
             txtNtpServer->set_sensitive(false);
         }
         else{
@@ -551,7 +553,7 @@ void MainWindow::enter_zone(){
             str_region=reg_text;
             string cmd = "";
             cmd = " ubconfig --target system set clock ZONE=" + str_region + "/" + str_zone;
-            system(cmd.c_str());
+            response_cmd=system(cmd.c_str());
         }
         else{
             str_zone="";
@@ -589,7 +591,7 @@ void MainWindow::enter_zone_glob(){
         if (!(zone_text.empty())){
         //str_zoneGlob = zone_text.substr(zone_text.find(") ")+2,zone_text.length());
             string cmd = "/usr/bin/ubconfig --target global set clock ZONE=" +reg_text +"/" + zone_text;
-            system(cmd.c_str());
+            response_cmd=system(cmd.c_str());
         }
         else{
             str_zoneGlob="";
@@ -709,7 +711,7 @@ void MainWindow::update_time_date(){
         if (str_data==str_data_entry){
             cmd = "date +%Y%m%d -s \"" + to_string(year)+
                 str_month+str_day+"\"";
-            system(cmd.c_str());
+            response_cmd=system(cmd.c_str());
             txtDate->set_text(str_data);
             year=0;
             month=0;
@@ -729,7 +731,7 @@ void MainWindow::update_time_date(){
     cmd = "date +%T -s \""+ 
         to_string(hour) + ":" + to_string(minute) 
         + ":" + to_string(ltm->tm_sec) +"\"";
-    system(cmd.c_str());
+    response_cmd=system(cmd.c_str());
 }
 
 void MainWindow::post_entry_data(){
diff --git a/source/ubl-settings-datetime.h b/source/ubl-settings-datetime.h
index c4164cc..a22dc6f 100644
--- a/source/ubl-settings-datetime.h
+++ b/source/ubl-settings-datetime.h
@@ -136,6 +136,7 @@ class MainWindow : public Gtk::ApplicationWindow {
         string strtxtNtpServer;
         string str_zone="";
         string str_zoneGlob;
+        int response_cmd;
         string array_region[14]={
             "Africa",
             "America",