This error occurs if you’re sending via SMTP. The SMTP server rejects the mail for several reasons: Your server dosen’t allow different sender and usernames Some servers require that the From email address is the same as the email address used to authenticate. Check your from name and match it to the username you use […]
Whenever you get a connection error when sending via SMTP like SMTP connect() failed. The most common reason for this problem is that your ESP (Email service provider) you have defined in your delivery settings doesn’t accept one of the used email addresses. Change the from, the reply-to and the bounce address to the email […]
In some cases your campaign pauses or you even not able to send mails at all caused by this error: SMTP Error: Could not authenticate. Your credentials are incorrect – double check them! One of your used email addresses are not permitted to use => Use the one you use to authenticate. You probably have […]
SMTP (Simple Mail Transfer Protocol) uses different ports to send mails. Sometime your provider block specific ports and you’re not able to send via SMTP. Some providers also allow only sending only via their own SMTP server and block others completely. The most common ports are 25, 993, 465, 587 for outgoing SMTP connection. To […]
Although it’s not recommended to use GoDaddy’s own email servers you can do it but have to follow some rules: GoDaddy has a limit of 250 mails from a certain account so make sure you setup the sending limits correctly. Use this form to calculate your values. You have to make sure the used from […]
When Mailster sends an email via your chosen delivery method it always relies on the response of your sending server. Sometimes the message has been sent but not actually delivered.
With SparkPost you get a solid delivery provider and 100.000 15.000 * mails per month for free. There’s some setup required before you can use this service though.
SendGrid is a powerfully sending provider which work with Mailster.