As you might know that sending email notifications or newsletter is a key to drive more membership and engagement to any community. We have been using a third party email newsletter/auto responder email marketing system and it has been costing a lot of money.
Do you know what are the best methods (websites, tools, software, manual??) to test if emails sent from our server is delivered to all email clients: Yahoo mail, gmail, google apps, hotmail, outlook, apple, exchange servers etc.