diff --git a/client/dialog.py b/client/dialog.py
index c2aefdf..0ac0e1e 100644
--- a/client/dialog.py
+++ b/client/dialog.py
@@ -73,14 +73,15 @@ class ConnectionDialog(QDialog, Ui_ConnectionDialog):
 
     @property
     def settings(self) -> ConnectionOptions:
-        return ConnectionOptions(ip=self.server_address_input.text(),
-                                 port=int(self.port_input.text()),
+        return ConnectionOptions(ip=self.server_address_input.text() or constants.DEFAULT_IP,
+                                 port=int(self.port_input.text() or constants.DEFAULT_PORT),
                                  nickname=self.nickname_input.text(),
                                  password=self.password_input.text(),
                                  remember=self.remember_checkbox.checkState())
 
     def validation(self, full: bool = True) -> None:
         address, port = self.validate_address()
+        nickname = self.validate_nickname()
 
         if not address and not port:
             self.status_bar.showMessage('Please fill in a valid server address and port.', 3000)
@@ -88,10 +89,11 @@ class ConnectionDialog(QDialog, Ui_ConnectionDialog):
             self.status_bar.showMessage('Please fill in a valid server address.', 3000)
         elif not port:
             self.status_bar.showMessage('Please fill in a valid port number.', 3000)
-        elif full and not self.validate_nickname():
+        elif full and not nickname:
             self.status_bar.showMessage('Please use a valid nickname. Letters and digits, 3-15 characters long.', 3000)
 
-        self.connect_button.setDisabled(not (self.validate_address() and self.validate_nickname()))
+        self.connect_button.setDisabled(not (address and port and nickname))
+        self.test_connection_button.setDisabled(not (address and port))
 
     def validate_nickname(self) -> bool:
         """Returns True if the nickname follows the nickname guidelines requested."""
@@ -100,7 +102,7 @@ class ConnectionDialog(QDialog, Ui_ConnectionDialog):
     def validate_address(self) -> Tuple[bool, bool]:
         """Returns True if the server address and port combination is valid"""
         address = self.server_address_input.text() or constants.DEFAULT_IP
-        port = self.port_input.text() or constants.DEFAULT_PORT
+        port = self.port_input.text() or str(constants.DEFAULT_PORT)
 
         valid_address = len(address) > 0 and re.match(r'^\d{1,4}\.\d{1,4}\.\d{1,4}\.\d{1,4}|localhost$',
                                                       address) is not None
diff --git a/client/gui.py b/client/gui.py
index acd20af..120dc35 100644
--- a/client/gui.py
+++ b/client/gui.py
@@ -82,14 +82,7 @@ class MainWindow(QMainWindow, Ui_MainWindow):
         self.get_message_history()
 
     def closeEvent(self, event):
-        if self.nicknameDialog and not self.closed:
-            logger.debug('Closing nickname dialog before main window')
-            self.closed = True
-            self.nicknameDialog.close()
-        else:
-            self.receiveThread.stop()
-            self.connectionsListTimer.stop()
-
+        self.receiveThread.stop()
         event.accept()  # let the window close
 
     def eventFilter(self, obj, event) -> bool:
diff --git a/client/main.py b/client/main.py
index d18349e..e48237c 100644
--- a/client/main.py
+++ b/client/main.py
@@ -1,3 +1,4 @@
+import logging
 from typing import Tuple
 
 from PyQt5.QtWidgets import QApplication
@@ -5,16 +6,16 @@ from PyQt5.QtWidgets import QApplication
 from client.dialog import ConnectionDialog
 from client.gui import MainWindow
 
-
-# def connection_dialog() -> Tuple[str, int, str, str, bool]:
-#     connect_dialog = ConnectionDialog()
+logger = logging.getLogger(__file__)
 
 
 def main():
     app = QApplication([])
     app.setApplicationName("TCPChat Client")
     connect_dialog = ConnectionDialog()
-    # m = MainWindow()
     app.exec_()
+
     if connect_dialog.connect_pressed:
-        print(connect_dialog.settings)
+        settings = connect_dialog.settings
+        m = MainWindow(settings.ip, settings.port, settings.nickname)
+        app.exec_()
diff --git a/constants.py b/constants.py
index 7fbd75b..d3b075e 100644
--- a/constants.py
+++ b/constants.py
@@ -11,7 +11,7 @@ MINIMUM_CONTRAST = 4.65
 DATABASE = os.path.join(__BASE_DIR, 'messages.db')
 
 DEFAULT_IP = "127.0.0.1"
-DEFAULT_PORT = "5555"
+DEFAULT_PORT = 5555
 
 ConnectionOptions = namedtuple('ConnectionOptions', ['ip', 'port', 'nickname', 'password', 'remember'])