diff --git a/phpBB/install/database_update.php b/phpBB/install/database_update.php
index 399ad3429a..983b1b46c4 100644
--- a/phpBB/install/database_update.php
+++ b/phpBB/install/database_update.php
@@ -2171,6 +2171,26 @@ function change_database_data(&$no_updates, $version)
 				}
 			}
 
+			// Disable receiving pms for bots
+			$sql = 'SELECT user_id
+				FROM ' . BOTS_TABLE;
+			$result = $db->sql_query($sql);
+
+			$bot_user_ids = array();
+			while ($row = $db->sql_fetchrow($result))
+			{
+				$bot_user_ids[] = (int) $row['user_id'];
+			}
+			$db->sql_freeresult($result);
+
+			if (!empty($bot_user_ids))
+			{
+				$sql = 'UPDATE ' . USERS_TABLE . '
+					SET user_allow_pm = 0
+					WHERE ' . $db->sql_in_set('user_id', $bot_user_ids);
+				_sql($sql, $errored, $error_ary);
+			}
+
 			$no_updates = false;
 		break;
 	}
diff --git a/phpBB/install/install_install.php b/phpBB/install/install_install.php
index 67ebb8b1c5..0575b58d92 100644
--- a/phpBB/install/install_install.php
+++ b/phpBB/install/install_install.php
@@ -1859,6 +1859,7 @@ class install_install extends module
 				'user_timezone'			=> 0,
 				'user_dateformat'		=> $lang['default_dateformat'],
 				'user_allow_massemail'	=> 0,
+				'user_allow_pm'			=> 0,
 			);
 
 			$user_id = user_add($user_row);