Unfortunately, it can happen that emails do not reach the recipient. There are several possible causes, and here you will find the most common problems and solutions! If you are still experiencing problems after reading this manual, you can, for example, use the
Mail- Use
Tester . This tool helps you understand exactly why your email might be getting a bad rating.
We basically assume here that the emails are sent from an application (such as a contact form or order confirmation), and not via an email program such as Outlook or Thunderbird.
Microsoft is rejecting your email
Microsoft deserves a mention of its own because they are often strict with accepting email, especially towards Outlook, Office365, Hotmail, and Live users. You can experience this in two ways:
- Email is accepted, but does not arrive in the recipient's inbox.
- Email is rejected with an error message.
Unfortunately, Microsoft often does not give clear reasons. What we can do is submit a request to lift a possible block and ensure that our servers do not send spam. For important e-mails, we recommend using a specialized SMTP service, such as Sendgrid, SMTP2GO, Mandrill, or Mailgun.
A valid return path is missing
The return-path is an important field in the email header. If it is not correct, services such as Gmail may reject your email. Make sure this field contains the correct value, for example the sender address of your email.
For WordPress, Magento, Joomla, and other platforms, you can usually solve this via a plugin or setting.
DKIM is missing or invalid
Signing emails correctly with DKIM is almost mandatory these days. Check out our guides for Plesk and HPW to set up DKIM correctly. *(LINKS)*
SPF record is incorrect
An SPF record indicates which mail servers are allowed to send emails on behalf of your domain. Check whether you have included all the correct servers in your SPF record. You can adjust this yourself in our DNS manager.
Server on a blacklist
It happens that a server is on a blacklist because spam has been sent from it in the past. We monitor our servers to prevent this. If you use a different SMTP server, please contact the administrator to to check this.
Reverse DNS is missing
Make sure the mail server has a reverse DNS record (PTR record). This will prevent issues with email delivery.
Autoresponder loops
Autoresponders can cause problems if they keep automatically responding to other autoresponders, which can cause a never-ending stream of emails. Most modern systems prevent this, but it is something to be aware of.