How to ensure 100% delivery of letters?

Question

Email

There is a task: to send an offer to, say, 50 recipients. Or maybe a resume.
In the first case, a link appears in the letter, in the second - an attached pdf.

Sending either from your own server or from Gmail.

In practice, when sending from different servers (not in blacklists), and even manually one letter at a time from the Gmail web face, almost 100% of the letters go to spam.

What is the best way to do this so that you are guaranteed not to get into spam?

PS Is there any point in using mass mailing services, in addition to the provided tracking?

Answer 1

No way.
I’m already tired of explaining that the letter is the complete “property” of the node that received it and it can do anything with it - parse, parse, reassemble ...
spam criteria for node operators can be as many as you like, and no one can adequately match these criteria did not measure
- the presence of a link in the letter - fuck it, spam
- attachment from pdf - fuck it, spam
- letter from gmail - fuck it, spam
- ... - fuck it, spam

Answer 2

There is always a sense in statistics, but we must not forget one fact - 100% delivery does not exist in nature

Answer 3

Spammers are not liked, to the point that even legitimate mailings end up in spam.
As for me, create a letter for 1 person. It is advisable to insert your full name and some text that is more or less unique. dkim and other attributes of a legal letter are required.

Answer 4

send according to the rules - warming up the IP and that's all