diff --git a/htdocs/public/eventorganization/attendee_subscription.php b/htdocs/public/eventorganization/attendee_subscription.php
index a40c836f0b3..a7f68a7ddab 100644
--- a/htdocs/public/eventorganization/attendee_subscription.php
+++ b/htdocs/public/eventorganization/attendee_subscription.php
@@ -86,7 +86,7 @@ $id = dol_decode($encodedid, $dolibarr_main_instance_unique_id);
 $conference = new ConferenceOrBooth($db);
 $resultconf = $conference->fetch($id);
 if ($resultconf < 0) {
-	setEventMessages(null, $object->errors, "errors");
+	setEventMessages(null, $conference->errors, "errors");
 }
 
 $project = new Project($db);
@@ -295,21 +295,31 @@ if (empty($reshook) && $action == 'add') {
 		$db->commit();
 		global $dolibarr_main_url_root;
 		if (!empty(floatval($project->price_registration))) {
-			$facture = new Facture($db);
-			$facture->type = 0;
-			$facture->socid = $thirdparty->id;
-			$facture->paye = 0;
-			//@todo price and taxes to add
-			$tva = get_default_tva($mysoc, $thirdparty);
-			$facture->date = dol_now();
-			$resultfacture = $facture->create($user);
-			if ($resultfacture < 0) {
+			$productforinvoicerow = new Product($db);
+			$resultprod = $productforinvoicerow->fetch($conf->global->SERVICE_CONFERENCE_ATTENDEE_SUBSCRIPTION);
+			if ($resultprod < 0) {
 				$error++;
-				$errmsg .= $facture->error;
+				$errmsg .= $productforinvoicerow->error;
 			} else {
-				$redirection = $dolibarr_main_url_root.'/public/payment/newpayment.php?source=conferencesubscription&ref='.$confattendee->id;
-				Header("Location: ".$redirection);
-				exit;
+				$facture = new Facture($db);
+				$facture->type = 0;
+				$facture->socid = $thirdparty->id;
+				$facture->paye = 0;
+				// @todo complete
+				//$baseprice = $productforinvoicerow->
+				$facture->total_ht = 10;
+				$facture->total_vat = $productforinvoicerow->tva_tx*10;
+				$facture->total_ttc =  $facture->total_ht + $facture->total_ttc;
+				$facture->date = dol_now();
+				$resultfacture = $facture->create($user);
+				if ($resultfacture < 0) {
+					$error++;
+					$errmsg .= $facture->error;
+				} else {
+					$redirection = $dolibarr_main_url_root.'/public/payment/newpayment.php?source=conferencesubscription&ref='.$confattendee->id;
+					Header("Location: ".$redirection);
+					exit;
+				}
 			}
 		} else {
 			// No price has been set
diff --git a/htdocs/public/payment/newpayment.php b/htdocs/public/payment/newpayment.php
index 9fba38962b4..d4bf295db10 100644
--- a/htdocs/public/payment/newpayment.php
+++ b/htdocs/public/payment/newpayment.php
@@ -69,6 +69,9 @@ include_once DOL_DOCUMENT_ROOT.'/core/class/hookmanager.class.php';
 $hookmanager = new HookManager($db);
 $hookmanager->initHooks(array('newpayment'));
 
+// For encryption
+global $dolibarr_main_instance_unique_id;
+
 // Load translation files
 $langs->loadLangs(array("main", "other", "dict", "bills", "companies", "errors", "paybox", "paypal", "stripe")); // File with generic data
 
@@ -375,6 +378,9 @@ if ($action == 'dopayment') {
 			dol_syslog("SCRIPT_URI: ".(empty($_SERVER["SCRIPT_URI"]) ? '' : $_SERVER["SCRIPT_URI"]), LOG_DEBUG); // If defined script uri must match domain of PAYPAL_API_OK and PAYPAL_API_KO
 
 			// A redirect is added if API call successfull
+			if ($source == 'conferencesubscription') {
+				$PAYPAL_API_OK .= '&conferencesubscription='.dol_encode('subscriptionok'.$ref, $dolibarr_main_instance_unique_id);
+			}
 			$mesg = print_paypal_redirect($PAYPAL_API_PRICE, $PAYPAL_API_DEVISE, $PAYPAL_PAYMENT_TYPE, $PAYPAL_API_OK, $PAYPAL_API_KO, $FULLTAG);
 
 			// If we are here, it means the Paypal redirect was not done, so we show error message
@@ -393,6 +399,10 @@ if ($action == 'dopayment') {
 		$urlok = preg_replace('/securekey=[^&]+/', '', $urlok);
 		$urlko = preg_replace('/securekey=[^&]+/', '', $urlko);
 
+		if ($source == 'conferencesubscription') {
+			$urlok .= '&conferencesubscription='.dol_encode('subscriptionok'.$ref, $dolibarr_main_instance_unique_id);
+		}
+
 		$mesg = '';
 		if (empty($PRICE) || !is_numeric($PRICE)) {
 			$mesg = $langs->trans("ErrorFieldRequired", $langs->transnoentitiesnoconv("Amount"));
@@ -747,7 +757,9 @@ if ($action == 'charge' && !empty($conf->stripe->enabled)) {
 		header("Location: ".$urlko);
 		exit;
 	} else {
-		$attendee->setStatut(1);
+		if ($source == 'conferencesubscription') {
+			$urlok .= '&conferencesubscription='.dol_encode('subscriptionok'.$ref, $dolibarr_main_instance_unique_id);
+		}
 		header("Location: ".$urlok);
 		exit;
 	}
diff --git a/htdocs/public/payment/paymentok.php b/htdocs/public/payment/paymentok.php
index 1942635001f..7e11944c243 100644
--- a/htdocs/public/payment/paymentok.php
+++ b/htdocs/public/payment/paymentok.php
@@ -56,6 +56,8 @@ if (!empty($conf->paypal->enabled)) {
 	require_once DOL_DOCUMENT_ROOT.'/paypal/lib/paypalfunctions.lib.php';
 }
 
+global $dolibarr_main_instance_unique_id;
+
 $langs->loadLangs(array("main", "other", "dict", "bills", "companies", "paybox", "paypal"));
 
 // Clean parameters
@@ -105,6 +107,21 @@ $ref = GETPOST('ref');
 $suffix = GETPOST("suffix", 'aZ09');
 $membertypeid = GETPOST("membertypeid", 'int');
 
+$conferencesubscription = GETPOST('conferencesubscription');
+$uncryptedconferencesubscription = dol_decode($conferencesubscription, $dolibarr_main_instance_unique_id);
+$subscription = substr($uncryptedconferencesubscription, 0, strlen($uncryptedconferencesubscription)-strlen($ref));
+$reffrompayment = substr($uncryptedconferencesubscription, -strlen($ref), strlen($ref));
+
+// Validation of an attendee after his payment
+if ($subscription == 'subscriptionok' && $ref == $reffrompayment) {
+	$attendeetovalidate = new ConferenceOrBoothAttendee($db);
+	$resultattendee = $attendeetovalidate->fetch($ref);
+	if ($resultattendee < 0) {
+		setEventMessages(null, $attendeetovalidate->errors, "errors");
+	} else {
+		$attendeetovalidate->setStatut(1);
+	}
+}
 
 // Detect $paymentmethod
 $paymentmethod = '';