diff --git a/src/main/java/de/bixilon/minosoft/Minosoft.java b/src/main/java/de/bixilon/minosoft/Minosoft.java
index 48f72e968..ec6449abd 100644
--- a/src/main/java/de/bixilon/minosoft/Minosoft.java
+++ b/src/main/java/de/bixilon/minosoft/Minosoft.java
@@ -35,6 +35,7 @@ import de.bixilon.minosoft.util.task.Task;
 import de.bixilon.minosoft.util.task.TaskImportance;
 import javafx.application.Platform;
 import javafx.scene.control.Dialog;
+import javafx.scene.control.TextArea;
 import javafx.stage.Stage;
 
 import java.io.IOException;
@@ -56,21 +57,14 @@ public final class Minosoft {
 
         taskWorker.setFatalError((exception) -> {
             Log.fatal("Critical error occurred while preparing. Exit");
-            if (StartProgressWindow.toolkitLatch.getCount() == 2) {
-                try {
+            try {
+                if (StartProgressWindow.toolkitLatch.getCount() == 2) {
                     StartProgressWindow.start();
-                } catch (InterruptedException e2) {
-                    e2.printStackTrace();
-                    System.exit(1);
-                }
-            }
-            if (StartProgressWindow.toolkitLatch.getCount() > 0) {
-                try {
-                    StartProgressWindow.toolkitLatch.await();
-                } catch (InterruptedException e2) {
-                    e2.printStackTrace();
-                    System.exit(1);
                 }
+                StartProgressWindow.toolkitLatch.await();
+            } catch (InterruptedException e) {
+                e.printStackTrace();
+                System.exit(1);
             }
             // hide all other gui parts
             StartProgressWindow.hideDialog();
@@ -80,7 +74,10 @@ public final class Minosoft {
                 // Do not translate this, translations might fail to load...
                 dialog.setTitle("Critical Error");
                 dialog.setHeaderText("An error occurred while starting Minosoft");
-                dialog.setContentText(exception.getClass().getCanonicalName() + ": " + exception.getLocalizedMessage());
+                TextArea text = new TextArea(exception.getClass().getCanonicalName() + ": " + exception.getLocalizedMessage());
+                text.setEditable(false);
+                text.setWrapText(true);
+                dialog.getDialogPane().setContent(text);
 
                 Stage stage = (Stage) dialog.getDialogPane().getScene().getWindow();
                 stage.getIcons().add(GUITools.logo);
diff --git a/src/main/java/de/bixilon/minosoft/config/Configuration.java b/src/main/java/de/bixilon/minosoft/config/Configuration.java
index 7c3f6e119..410a23b81 100644
--- a/src/main/java/de/bixilon/minosoft/config/Configuration.java
+++ b/src/main/java/de/bixilon/minosoft/config/Configuration.java
@@ -187,7 +187,7 @@ public class Configuration {
         return config;
     }
 
-    private void migrateConfiguration() {
+    private void migrateConfiguration() throws ConfigMigrationException {
         int configVersion = getInt(ConfigurationPaths.IntegerPaths.GENERAL_CONFIG_VERSION);
         Log.info(String.format("Migrating config from version %d to  %d", configVersion, LATEST_CONFIG_VERSION));
         for (int nextVersion = configVersion + 1; nextVersion <= LATEST_CONFIG_VERSION; nextVersion++) {
@@ -199,10 +199,10 @@ public class Configuration {
 
     }
 
-    private void migrateConfiguration(int nextVersion) {
+    private void migrateConfiguration(int nextVersion) throws ConfigMigrationException {
         switch (nextVersion) {
             // ToDo
-            default -> throw new IllegalArgumentException("Can not migrate config: Unknown config version " + nextVersion);
+            default -> throw new ConfigMigrationException("Can not migrate config: Unknown config version " + nextVersion);
         }
     }
 }
diff --git a/src/main/java/de/bixilon/minosoft/util/Util.java b/src/main/java/de/bixilon/minosoft/util/Util.java
index 52907da93..e710c5b9c 100644
--- a/src/main/java/de/bixilon/minosoft/util/Util.java
+++ b/src/main/java/de/bixilon/minosoft/util/Util.java
@@ -253,12 +253,12 @@ public final class Util {
         return new ThreadFactoryBuilder().setNameFormat(threadName + "#%d").build();
     }
 
-    public static void createParentFolderIfNotExist(String file) {
-        createParentFolderIfNotExist(new File(file));
+    public static boolean createParentFolderIfNotExist(String file) {
+        return createParentFolderIfNotExist(new File(file));
     }
 
-    public static void createParentFolderIfNotExist(File file) {
-        file.getParentFile().mkdirs();
+    public static boolean createParentFolderIfNotExist(File file) {
+        return file.getParentFile().mkdirs();
     }
 
     public static String generateRandomString(int length) {