We’re using Exchange as our email distributor and having some difficulties with the reception of the filled out form on our website. We’ve used three email adresses and all exhibits the same symptoms: emails from email@example.com were received successfully at first but after april or so, they are not showing up anymore. No signs of them in the spam folders either. The email used is whitelisted in the Exchange domain admin panel. Forms are received sucessfully on a GMail account.