That's a wildly open question. Your first step is to look at the headers of a message you've sent on the received end. Most anti-spam filters leave artifacts in the headers and my guess is that will lead you to something you can change about your mail server to make your messages look less "spammy".
Remember that it's not in the mail providers interest to file legit messages under spam, so if you're not an actual spammer you should be able to find a way to people's inboxes. There are also about a zillion articles on how to not be caught by spam filters. Just google. HTH, Scott ________________________________ From: owner-postfix-us...@postfix.org <owner-postfix-us...@postfix.org> on behalf of Jason Long <hack3r...@yahoo.com> Sent: October 12, 2020 2:07 PM To: postfix-users@postfix.org <postfix-users@postfix.org> Subject: Why emails sending to Spam? Hello, Why I sending email from my server to Yahoo! Or Gmail, then it sent to Spam and not Inbox folder? I checked my server IP by "https://mxtoolbox.com/blacklists.aspx"; and everything is OK. Thank you.
