For Exchange and Office 365 calendar we use this module https://www.vtextra.com/en/ecommerce-vtiger-modules/modules/product/9-vtiger-exchange-sync.html ----- CentOS 6.5 vtiger 7.0.1 -- Sent from: http://vtiger-crm.2324883.n4.nabble.com/vtigercrm-developers-f4.html