diff --git a/htdocs/public/paybox/paymentko.php b/htdocs/public/paybox/paymentko.php
index c4457ff4d93..6316ad55434 100644
--- a/htdocs/public/paybox/paymentko.php
+++ b/htdocs/public/paybox/paymentko.php
@@ -64,7 +64,7 @@ dol_syslog("POST=".$tracepost, LOG_DEBUG, 0, '_paybox');
 
 
 // Send an email
-if (! empty($conf->global->MEMBER_PAYONLINE_SENDEMAIL) && preg_match('/MEM=',$fulltag))
+if (! empty($conf->global->MEMBER_PAYONLINE_SENDEMAIL) && preg_match('/MEM=/',$fulltag))
 {
 	$sendto=$conf->global->MEMBER_PAYONLINE_SENDEMAIL;
 	$from=$conf->global->MAILING_EMAIL_FROM;
diff --git a/htdocs/public/paybox/paymentok.php b/htdocs/public/paybox/paymentok.php
index b8940fa1a32..a093a28bbf0 100644
--- a/htdocs/public/paybox/paymentok.php
+++ b/htdocs/public/paybox/paymentok.php
@@ -94,7 +94,7 @@ dol_syslog("Call newpaymentok with token=".$token." paymentType=".$paymentType."
 */
 
 // Send an email
-if (! empty($conf->global->MEMBER_PAYONLINE_SENDEMAIL) && preg_match('/MEM=',$fulltag))
+if (! empty($conf->global->MEMBER_PAYONLINE_SENDEMAIL) && preg_match('/MEM=/',$fulltag))
 {
 	$sendto=$conf->global->MEMBER_PAYONLINE_SENDEMAIL;
 	$from=$conf->global->MAILING_EMAIL_FROM;
diff --git a/htdocs/public/paypal/paymentko.php b/htdocs/public/paypal/paymentko.php
index 21d93f3eaa1..c2412a8a20b 100755
--- a/htdocs/public/paypal/paymentko.php
+++ b/htdocs/public/paypal/paymentko.php
@@ -72,7 +72,7 @@ dol_syslog("POST=".$tracepost, LOG_DEBUG, 0, '_paypal');
 
 
 // Send an email
-if (! empty($conf->global->MEMBER_PAYONLINE_SENDEMAIL) && preg_match('/MEM=',$fulltag))
+if (! empty($conf->global->MEMBER_PAYONLINE_SENDEMAIL) && preg_match('/MEM=/',$fulltag))
 {
 	$sendto=$conf->global->MEMBER_PAYONLINE_SENDEMAIL;
 	$from=$conf->global->MAILING_EMAIL_FROM;
diff --git a/htdocs/public/paypal/paymentok.php b/htdocs/public/paypal/paymentok.php
index e4ea8a92095..173052318e9 100755
--- a/htdocs/public/paypal/paymentok.php
+++ b/htdocs/public/paypal/paymentok.php
@@ -131,7 +131,7 @@ if ($PAYPALTOKEN)
 
 
 	// Send an email
-	if (! empty($conf->global->MEMBER_PAYONLINE_SENDEMAIL) && preg_match('/MEM=',$fulltag))
+	if (! empty($conf->global->MEMBER_PAYONLINE_SENDEMAIL) && preg_match('/MEM=/',$fulltag))
 	{
 		$sendto=$conf->global->MEMBER_PAYONLINE_SENDEMAIL;
 		$from=$conf->global->MAILING_EMAIL_FROM;