Problems with sending email can have many causes. With the help of this article, you should be able to narrow down and solve the problem.
Do you have problems receiving emails? The article Receiving Emails Not Possible will help you to solve the problem.
IONOS Login and Server Data for POP3/IMAP Unknown
The IONOS login and server data for POP3 or IMAP are not known to you.
You can use your IONOS email address with any email program, such as Microsoft Outlook or Mozilla Thunderbird, on your computer or smartphone. The necessary settings, e.g. server address or port, are summarized in the article Settings for your email program (IMAP & POP3).
Undeliverability (Bounce) Message on Email as IONOS Customer
You are an IONOS customer. After sending an email using your IONOS email address, you received a bounce message.
If one of your emails cannot be delivered, you will receive an email with a status code. This status code informs you about the reasons for the undeliverability. The article Error messages for undeliverable emails lists the status codes and provides you with possible solutions.
Undeliverability (Bounce) Message on Email as a Non-IONOS Customer
You have your email account with an alternative email provider. After sending an email to an IONOS email address, you received a bounce message.
If an email you send to an IONOS customer cannot be delivered, you will receive an email with a status code. This status code informs you about the reasons for the undeliverability. The article SMTP error messages of the IONOS mail servers lists the status codes and provides you with possible solutions.
Error Message from Email Program on Computer or Smartphone
When you send an email through the email program on your computer or smartphone, you receive an error message from the program.
Use the IONOS configuration guides to check the settings of your email program. Instructions can be found in the Help Center under the drop-down list boxes on the Email > My Email overview page:
- Microsoft Outlook
- Using email on Android smartphones
- Using email on Apple iPhone/iPad
- Other email programs
If errors occur despite correct setup of the email program, please read the background information in the program help of your email program or on the manufacturer's website.
Your Email Program Does Not Support TLS 1.2
Email access either without encryption and through the TLS 1.0 and TLS 1.1 protocols have become deprecated, meaning they do not meet current security standards. Access to our email servers by any of these methods will be disabled in order to protect your email communications. In order for the transmission of emails between your device/email program and our email servers to continue working, they must support the TLS 1.2 protocol or higher and encryption (SSL/TLS) must be activated.
Check the documentation for your device or email program to see if it supports TLS 1.2. If necessary, update the software in question. The latest versions of the most common email programs support the more secure versions of TLS 1.2 and TLS 1.3.
You should also make sure that encryption (SSL/TLS) is enabled on your device or email program. The next section explains the proper settings you should use.
For more information, please read this article describing how to enable SSL encryption in an email program, including a list of more specific articles that describe how to configure SSL encryption in the most common email programs (Outlook, Thunderbird, Apple Mail, etc.).
Email Transmission Successful - No Delivery
Your email was sent successfully and without an error message. However, the email is not delivered to the recipient.
In this case, the problem does not necessarily have to be on your side. Notify the recipient of the email about the Help Center article Receiving email not possible. Suggest a check based on the solutions presented to rule out a problem on the recipient side.
Check whether security software on your computer or smartphone, such as a firewall or virus scanner, is interfering with or blocking the sending of email. Issue the appropriate approvals for sending emails. You can find details on this in the program help or on the manufacturer's website.