diff --git a/Project.Controller/AppController.cs b/Project.Controller/AppController.cs
index c656947..6b23eee 100644
--- a/Project.Controller/AppController.cs
+++ b/Project.Controller/AppController.cs
@@ -2,7 +2,7 @@
 using Project.Model;
 namespace Project.Controller;
 
-public class AppController
+public partial class AppController
 {
     public static void NewLoginSave(string username, string password, string email)
     {
diff --git a/Project.Controller/InputSanitizer.cs b/Project.Controller/InputSanitizer.cs
new file mode 100644
index 0000000..4c321d1
--- /dev/null
+++ b/Project.Controller/InputSanitizer.cs
@@ -0,0 +1,23 @@
+namespace Project.Controller;
+
+public class InputSanitizer
+{
+    public static bool MasterLoginPasswordBool(string password)
+    {
+        if (string.IsNullOrEmpty(password) || password.Length < 6) return false;           
+        else return true;
+    }
+    
+    public static bool MasterLoginEmailBool(string email)
+    {
+        if (string.IsNullOrEmpty(email)) return false;
+        if (email.Contains('@') && email.Length > 6) return true;
+        else return false;
+    }
+    
+    public static bool MasterLoginNameBool(string username)
+    {
+        if (string.IsNullOrEmpty(username) || username.Length < 4) return false;
+        else return true;
+    }
+}
\ No newline at end of file
diff --git a/Project.View/NewLogin/NewLogin.axaml.cs b/Project.View/NewLogin/NewLogin.axaml.cs
index c5abe36..d047fa2 100644
--- a/Project.View/NewLogin/NewLogin.axaml.cs
+++ b/Project.View/NewLogin/NewLogin.axaml.cs
@@ -23,12 +23,23 @@ public partial class NewLogin : Window
 
     private void NewLoginSaveOnClick(object? sender, RoutedEventArgs e)
     {
-        string username = NewLoginUsernameBox.Text?.Trim();
-        string password = NewLoginPasswordBox.Text?.Trim();
-        string email = NewLoginEmailBox.Text?.Trim();
+        string username = NewLoginUsernameBox.Text?.Trim() ?? string.Empty;
+        string password = NewLoginPasswordBox.Text?.Trim() ?? string.Empty;
+        string email = NewLoginEmailBox.Text?.Trim() ?? string.Empty;
+        //test inputs:
+        bool masterLoginPasswordBool = InputSanitizer.MasterLoginPasswordBool(password);
+        bool masterLoginEmailBool = InputSanitizer.MasterLoginEmailBool(email);
+        bool masterLoginNameBool = InputSanitizer.MasterLoginNameBool(username);
         //give strings to appcontroller and keep working on them there
-        AppController.NewLoginSave(username, password, email);
-        Close();
+        if (masterLoginPasswordBool || masterLoginEmailBool || masterLoginNameBool)
+        {
+            AppController.NewLoginSave(username, password, email);
+            Close();
+        }
+        else
+        {
+            
+        }
     }
     
     private void NewLoginCancelOnClick(object? sender, RoutedEventArgs e)