My setup:

• Rules
• Mail system
• HTML mail
• Mime mail

Now I am sending an e-mails via rules “Send HTML e-mail” action.

Everything works fine, if receiver is having gmail email address. Meaning, in our country there are a lot of email hosting companies, and two of them (centrum.cz, email.cz) are having majority of email addresses. In those cases, rules mails sometimes does not come at all.

What I have noticed is, that basic drupal mails about account creation (invitation mail) does come everytime, but rules mails does not.

Note that website URL is not the same as email suffix emails are coming from (for testing, it will be the same url in production).

Having trouble setting this up properly, first time email is received in gmail account, it falls to spam folder (because of difference between email address and url), maybe those “email providers” which are so popular in my country does not even send it to spam folder, but removes the emails completely.

Any ideas where to look for? What should I set up? Any advice would be appreciated.