diff --git a/Makefile b/Makefile
index 732dd1e2f..2c7110355 100644
--- a/Makefile
+++ b/Makefile
@@ -637,7 +637,7 @@ install_uwsgi_server:
 	@install -v -d $(RUWSGIYAMLDIR) $(RLLNGAPPDIR)
 	@install -m 644 -v fastcgi-server/uwsgi/llng-server.yaml $(RUWSGIYAMLDIR)/llng-server.yaml
 	@install -m 644 -v $(SRCHANDLERDIR)/eg/llng-server.psgi $(RLLNGAPPDIR)/llng-server.psgi
-	$(PERL) -pi -e 's#__APPDIR__#$(LLNGAPPDIR)#' $(RUWSGIYAMLDIR)/llng-server.yaml
+	$(PERL) -pi -e 's#__APPDIR__#$(LLNGAPPDIR)#;s#__UID__#$(UWSGIUSER)#;s#__GID__#$(UWSGIGROUP)#;' $(RUWSGIYAMLDIR)/llng-server.yaml
 
 # Site install
 
diff --git a/e2e-tests/test-nginx.conf b/e2e-tests/test-nginx.conf
index f26865242..2995defdf 100644
--- a/e2e-tests/test-nginx.conf
+++ b/e2e-tests/test-nginx.conf
@@ -18,6 +18,14 @@ server {
 
     # Keep original request (LLNG server will received /llauth)
     fastcgi_param X_ORIGINAL_URI  $request_uri;
+
+    # OU TO USE uWSGI
+    #include /etc/nginx/uwsgi_params;
+    #uwsgi_pass 127.0.0.1:5000;
+    #uwsgi_pass_request_body  off;
+    #uwsgi_param CONTENT_LENGTH "";
+    #uwsgi_param HOST $http_host;
+    #uwsgi_param X_ORIGINAL_URI  $request_uri;
   }
 
   # Client requests
diff --git a/fastcgi-server/uwsgi/llng-server.yaml b/fastcgi-server/uwsgi/llng-server.yaml
index ea1a4c4ea..84079a31f 100644
--- a/fastcgi-server/uwsgi/llng-server.yaml
+++ b/fastcgi-server/uwsgi/llng-server.yaml
@@ -3,3 +3,5 @@ uwsgi:
         socket: 127.0.0.1:5000
         psgi: __APPDIR__/llng-server.psgi
         master: true
+        uid: __UID__
+        gid: __GID__
diff --git a/lemonldap-ng-portal/lib/Lemonldap/NG/Portal/2F/Engines/Default.pm b/lemonldap-ng-portal/lib/Lemonldap/NG/Portal/2F/Engines/Default.pm
index b4ed3f2b0..4458fc8e7 100644
--- a/lemonldap-ng-portal/lib/Lemonldap/NG/Portal/2F/Engines/Default.pm
+++ b/lemonldap-ng-portal/lib/Lemonldap/NG/Portal/2F/Engines/Default.pm
@@ -3,7 +3,7 @@
 # 2FA engine provides 3 functions and 1 interface:
 #  - init()
 #  - run($req): called during auth process after session populating
-#  - dysplay2fRegisters($req, $session): indicates if a 2F registration is
+#  - display2fRegisters($req, $session): indicates if a 2F registration is
 #                                        available for this user
 #  - /2fregisters: the URL path that displays 2F registration menu
 
@@ -164,11 +164,11 @@ sub run {
     return PE_SENDRESPONSE;
 }
 
-# bool public dysplay2fRegisters($req, $session)
+# bool public display2fRegisters($req, $session)
 #
 # Return true if at least 1 register module is available for this user. Used
 # by Menu to display or not /2fregisters page
-sub dysplay2fRegisters {
+sub display2fRegisters {
     my($self,$req,$session) = @_;
     foreach my $m ( @{ $self->sfRModules } ) {
         return 1 if ( $m->{r}->( $req, $session) );
diff --git a/lemonldap-ng-portal/lib/Lemonldap/NG/Portal/2F/Register/Yubikey.pm b/lemonldap-ng-portal/lib/Lemonldap/NG/Portal/2F/Register/Yubikey.pm
index ba14a97a9..e53bb8d6d 100644
--- a/lemonldap-ng-portal/lib/Lemonldap/NG/Portal/2F/Register/Yubikey.pm
+++ b/lemonldap-ng-portal/lib/Lemonldap/NG/Portal/2F/Register/Yubikey.pm
@@ -5,7 +5,6 @@ use Mouse;
 use Lemonldap::NG::Portal::Main::Constants qw(
   PE_FORMEMPTY
   PE_ERROR
-  PE_OK
 );
 
 our $VERSION = '2.0.0';
@@ -36,17 +35,36 @@ sub run {
         if ( $otp and length($otp) > 12 ) {
             my $keys = $req->userData->{_yubikeys} || '';
             $keys .= ( $keys ? ', ' : '' )
-              . substr( $otp, 0, $self->conf->{yubikeyPublicIDSize} );
+              . substr( $otp, 0, $self->conf->{yubikey2fPublicIDSize} );
             $self->p->updatePersistentSession( $req, { _yubikeys => $keys } );
+            return $self->p->sendHtml(
+                $req, 'error',
+                params => {
+                    RAW_ERROR      => 'yourKeyIsRegistered',
+                    AUTH_ERROR_TYPE => 'positive',
+                }
+            );
         }
         else {
             $self->userLogger->error('Yubikey 2F: no code');
-            return PE_FORMEMPTY;
+            return $self->p->sendHtml(
+                $req, 'error',
+                params => {
+                    AUTH_ERROR      => PE_FORMEMPTY,
+                    AUTH_ERROR_TYPE => 'positive',
+                }
+            );
         }
     }
     else {
         $self->userLogger->error("Unknown Yubikey action $action");
-        return PE_ERROR;
+        return $self->p->sendHtml(
+            $req, 'error',
+            params => {
+                AUTH_ERROR      => PE_ERROR,
+                AUTH_ERROR_TYPE => 'positive',
+            }
+        );
     }
 }
 
diff --git a/lemonldap-ng-portal/lib/Lemonldap/NG/Portal/2F/Yubikey.pm b/lemonldap-ng-portal/lib/Lemonldap/NG/Portal/2F/Yubikey.pm
index c26da7013..53460eae0 100644
--- a/lemonldap-ng-portal/lib/Lemonldap/NG/Portal/2F/Yubikey.pm
+++ b/lemonldap-ng-portal/lib/Lemonldap/NG/Portal/2F/Yubikey.pm
@@ -36,8 +36,7 @@ sub init {
     unless ($self->conf->{yubikey2fClientID}
         and $self->conf->{yubikey2fSecretKey} )
     {
-        $self->logger->error(
-            "Missing mandatory parameters (Client ID and secret key)");
+        $self->error('Missing mandatory parameters (Client ID and secret key)');
         return 0;
     }
     $self->conf->{yubikey2fPublicIDSize} ||= 12;
@@ -92,8 +91,8 @@ sub verify {
 
     # Verify OTP
     if (
-        index( substr( $code, 0, $self->conf->{yubikey2fPublicIDSize} ),
-            $session->{_yubikeys} ) == -1
+        index( $session->{_yubikeys},
+            substr( $code, 0, $self->conf->{yubikey2fPublicIDSize} ) ) == -1
       )
     {
         $self->userLogger->warn('Yubikey not registered');
diff --git a/lemonldap-ng-portal/site/templates/bootstrap/error.tpl b/lemonldap-ng-portal/site/templates/bootstrap/error.tpl
index b79b4a652..b079edfd7 100644
--- a/lemonldap-ng-portal/site/templates/bootstrap/error.tpl
+++ b/lemonldap-ng-portal/site/templates/bootstrap/error.tpl
@@ -3,6 +3,9 @@
   <TMPL_IF AUTH_ERROR>
     <div class="message message-<TMPL_VAR NAME="AUTH_ERROR_TYPE"> alert"><span trmsg="<TMPL_VAR NAME="AUTH_ERROR">"></span></div>
   </TMPL_IF>
+  <TMPL_IF RAW_ERROR>
+    <div class="message message-<TMPL_VAR NAME="AUTH_ERROR_TYPE"> alert"><span trspan="<TMPL_VAR NAME="RAW_ERROR">"></span></div>
+  </TMPL_IF>
   <TMPL_IF ERROR403>
     <div class="message message-negative alert">
       <span trspan="accessDenied">You have no access authorization for this application</span>