I hope that someone is able to help. Our company has gone through a name change and we wish to update all of out customers. We have a few thousand that we want to email and also send an attachment.
I can remember a few people sending out large mails before and us being blacklisted. What's the best way to send out this email? I have been looking at companies like mail chimp and testing this but my only worry was when I received the email it was marked as spam.