diff --git a/app/__init__.py b/app/__init__.py
index 7753b037d2ce7ebe36328a8061524473dd2c39c2..5dd8c419a0bb3f06ec7aede55ab0b4ec0d23f2db 100644
--- a/app/__init__.py
+++ b/app/__init__.py
@@ -34,6 +34,8 @@ def create_app(config_name):
     @app.route('/', methods=['GET', 'POST']) # initial route to display the reg page
     def index():
 
+        invalid_state = ["blocked", "certification"]
+
         if 'uid' not in session:
             session['uid']=str(uuid.uuid4())
 
@@ -48,7 +50,11 @@ def create_app(config_name):
         else:
             session['return_url'] = request.referrer
 
-        return render_template('auth/SignUp.html', room_id=session['uid'],
+        if rc_util.check_state(session['user'].get('username')) in invalid_state:
+            return render_template('errors/error.html', title='account creation failed')
+        
+        else:
+            return render_template('auth/SignUp.html', room_id=session['uid'],
                                username=session['user'].get('username'),
                                fullname=session['user'].get('fullname'), email=session['user'].get('email'),
                                referrer=session['return_url'], cancel_url=vars.default_referrer,