Unfortunately it can happen that your mass mailings end up as spam or are rejected by the recipients' server. Often this is not related to a malfunctioning of our SMTP server, but caused instead by some bad practices, often applied unconsciously.
So here's a checklist of what you should verify first and foremost:

1. Configure your DNS.
This is extremely important. Configuring your DNS records with turboSMTP details is essential to ensure the best delivery rate and avoid to be filtered out by incoming servers. The procedure is extensively explained on this page.

2. Control your subject line.
A mass email's subject line should never contain spammy words and symbols such as "Cash", "$", "£", "Millions", "Mortgage", "Cheap meds", "Easy income", or even "Free gift". Multiple exclamation points (!!!) and ALL CAPS is should be absolutely avoided as well.

3. Don't use a free email account as a sender.
Antispam filters consider mass emails coming from free email accounts (e.g. @gmail.com, @hotmail.com, @yahoo.com etc.) very likely to be spam. This happens because actual spammers use these free email providers to spread junk messages. That's why we highly recommend to use turboSMTP only with domain-related sender address (e.g. @yourwebsite.com); if you don't, the global delivery rates may drop significantly.

4. Write proper content.
If the content of your newsletter is badly written, with non-consistent phrases and full of typos or grammar errors, an incoming server is more likely to consider it as a spam message. Also, your newsletter should always contain some text. Images and words must find a proper balance, and in any case never sand an image-only email.

5. Always provide an unsubscribe link.
If you don't, any people who want to opt out from your list will simply throw your email in the junk folder.

6. Clean your lists.
If you keep sending to non-existent, doubled or wrong addresses, you will get loads of hard bounces and your delivery rate will surely be affected. Take some time to clean your lists, erasing at least any non-existent contacts.

7. Is your domain blacklisted?
The quickest way to check if you're on some blacklist is to use MX Toolbox and in case ask for a removal.

If after all that your emails are still being filtered out or considered as spam, please contact us and we'll be happy to help you!