I have a dedicated server, with few small projects as a corporative local websites for local companies in south spain.
In the past, with other dedicated server, all the emails were considered spam, even in the first email they send. The IP is not blacklister.
How can I do to warranty that our emails are not going to be spam anymore? I hear / read something like I have to sign the emails or pay a kind of montly fee to get some kind of certificate.
Someone can help me please?
Thanks a lot!