Don't know where to turn with this question, but I think Habr will help.
In the field of my work, I often send the same type pisma (letters with one header, one text message with one attached file). Now it's all done manually, once or twice a month I have to send a day about 200-300 emails, sometimes under 500.
I would like to automate this process. Preferably free of course, but here's how it goes :)
So, please advise what and how to automate this? (software, service or something else?)
No spam, no junk e-mail, it's strictly business correspondence, in these letters, people are interested. So everything is fair.