Please note the following when sending emails to 1&1 IONOS mailboxes:
1&1 IONOS reserves the right to temporarily or permanently refuse to accept emails if at least one of the following points is not fulfilled for the protection of its users and 1&1 IONOS systems:
- The sender of emails must respect the legal requirements of his country, as long as these do not contradict the requirements set out here. For senders from the USA, this is primarily compliance with the Can-Spam Act.
- The sender must comply with the standards required by RFC 5321 and RFC 5322.
- The technical information used in the email (email header) and the sender's details must not be forged. The recipient must be able to see who the actual sender of the email is.
- The sending server must have a static IP address. This must also be configured correctly. This concerns in particular the correct reverse DNS entry of the IP address used.
- The receipt of emails with harmful, immoral or illegal contents is rejected. These are in particular virus- or trojan-infected emails as well as those that refer to virus- or trojan-infected pages. Emails with content that serves incitement of the people to commit crimes, glorify violence or emails that refer to pages with such content. Emails that are aimed at illegally obtaining the recipient's access data will also be rejected.
- Mass emails or emails with commercial content may only be sent to users whose explicit consent has been obtained. It must be made easy for the recipient to object to the further sending of such emails.
- Mass mails or emails with commercial content must contain a valid imprint. This includes valid, non-electronic contact information such as the complete real address and telephone number.
- The sender must ensure that addresses of users who no longer exist are not used again.
1&1 IONOS reserves the right to use external lists such as IP lists (RBL lists) or hash lists to sort and reject emails.
Furthermore, 1&1 IONOS reserves the right to take legal action against senders who violate this email policy or to temporarily or permanently prevent the receipt of emails from the sender.