diff --git a/src/fr/univ/lyon1/gui/controller/ApplicationController.java b/src/fr/univ/lyon1/gui/controller/ApplicationController.java
index dd3a3cb..337f1e9 100644
--- a/src/fr/univ/lyon1/gui/controller/ApplicationController.java
+++ b/src/fr/univ/lyon1/gui/controller/ApplicationController.java
@@ -7,7 +7,9 @@ import fr.univ.lyon1.common.ServerConfiguration;
 import fr.univ.lyon1.common.command.Command;
 import fr.univ.lyon1.common.command.CommandType;
 import fr.univ.lyon1.common.exception.ChatException;
+import fr.univ.lyon1.common.exception.LoginInvalid;
 import fr.univ.lyon1.common.exception.UnknownCommand;
+import fr.univ.lyon1.gui.handlers.ServerConfigurationHandler;
 import javafx.application.Platform;
 import javafx.fxml.FXML;
 import javafx.scene.control.TextArea;
@@ -17,6 +19,7 @@ import javafx.scene.layout.VBox;
 import javafx.scene.paint.Color;
 import javafx.scene.text.Text;
 import javafx.scene.text.TextFlow;
+import javafx.stage.Stage;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
@@ -135,10 +138,25 @@ public class ApplicationController {
                                     }
                                 }
                             }
+                        } else if (object instanceof LoginInvalid) {
+                            // TODO: Invalid login
+                            Platform.runLater(() -> {
+                                try {
+                                    this.closeSocket();
+
+                                    @NotNull
+                                    final Stage stage = (Stage) this.vboxChannelsList.getScene().getWindow();
+                                    new ServerConfigurationHandler().launch(stage);
+                                } catch (IOException e) {
+                                    e.printStackTrace();
+                                }
+                            });
                         } else if (object instanceof ChatException) {
+                            System.out.println("?");
                             ((ChatException) object).printStackTrace();
-                        } else
+                        } else {
                             this.sendObject(new UnknownCommand());
+                        }
                     } else {
                         try {
                             this.closeSocket();
@@ -156,8 +174,6 @@ public class ApplicationController {
                             ex.printStackTrace();
                         }
                     }
-
-                    e.printStackTrace();
                 }
             }
         });
diff --git a/src/fr/univ/lyon1/server/ConnectedClient.java b/src/fr/univ/lyon1/server/ConnectedClient.java
index 09f98c6..20200a7 100644
--- a/src/fr/univ/lyon1/server/ConnectedClient.java
+++ b/src/fr/univ/lyon1/server/ConnectedClient.java
@@ -122,7 +122,8 @@ public class ConnectedClient implements Runnable {
                         actionCommand((Command) data);
                     else
                         throw new UnknownCommand();
-                } catch (ChatException e) {
+                } catch (IOException | ChatException e) {
+                    System.out.println("Error server " + e.getLocalizedMessage());
                     out.writeObject(e);
                     out.flush();
                 }