问题
I have an application built in PHP/Symfony. Part of it requires sending what is essentially an account verification email to users. Unfortunately, it seems that my email is triggering spam filters (gmail, hotmail, probably others) and not making it to the users inboxes.
What strategies can I use to avoid being filtered?
回答1:
Rather than sending mail from the server where your website runs, it's better to use trusted external mail server. You can do that with Swift_SmtpTransport.
You can even use your gmail account for that purpose: http://www.symfony-project.org/more-with-symfony/1_4/en/04-Emails#chapter_04_sub_sending_emails_via_gmail
回答2:
Email filters use different strategies for detecting autogenerated emails. Each email filter is different, but your best strategy would be to make sure that you actually creates an email that complies stricktly to the email standard. Include all relevant headers. Make sure that you use the correct encoding for international charachters etc. A well formed email will usually get a better score.
And of course use an email proxy with a good reputation.
来源：https://stackoverflow.com/questions/5096971/avoiding-spam-filters-for-account-confirmation-emails