Verified email dispatch with S/MIMESign your emails digitally
The S/MIME feature is optionally available in EMM – for maximum security and trust when sending sensitive emails. With the help of a digital signature, you can give your recipients a clear answer to the question: “Is this sender trustworthy?”. Protect your brand and your customers from manipulation, spoofing and data misuse – automatically and professionally with S/MIME certification.
The main advantages of S/MIME in EMM:
- Verified sender: If you add a digital signature to your email using S/MIME, you are automatically verified as the sender
- Protection against fraudsters: The signature with S/MIME ensures your recipients that the content of your mailings has not been altered or falsified by third parties.
- Compliance with legal requirements: increased security of your communication through a personal certificate (particularly relevant for the financial and healthcare sectors)
- Improved reputation: by proving your trustworthiness to recipients
Are you already using S/MIME?
How does S/MIME work?
Perhaps you have already asked yourself whether an email you have received is really credible. Is the sender really who they say they are? Can I open the links in this email without worrying? Especially if the email asks for personal information via a link, you should be sure that it is not a fake email.
You can use S/MIME – short for “Secure / Multipurpose Internet Mail Extension” – so that your customers no longer have to ask themselves these questions when they receive your emails.

How S/MIME works:
If you opt for S/MIME, your sender address will be confirmed with a certified digital signature for a specific period of time. By signing your mailing with S/MIME, recipients can check the certificate for your signature, which identifies you as a trustworthy and legitimate sender.
Your S/MIME certificate is delivered as an attachment to your mailings. Some email programs then show the recipients a small icon at the top of the email, which indicates at first glance that your address is certified. In other cases, you will find a corresponding icon in the header of your email. IN addition, there is a link that allows you to view the exact certificate. Some programs only display the S/MIME certificate as a file attachment.
As the appearance varies depending on the email client, you can find some examples here:
Outlook – Signature with S/MIME
Gmail – Signature with S/MIME
Thunderbird – Signature with S/MIME
Apple Mail – Signature with S/MIME
S/MIME
- S/MIME = Secure / Multipurpose Internet Mail Extensions
- Main function: Digital signature of the sender address of emails
- Digital signature: Content and attachment signed with personal certificate
- Visibility: Yes, email clients usually display a seal
DKIM
- DKIM = DomainKeys Identified Mail
- Main function: Digital signature of the email header to verify the sending domain
- Digital signature: only certain header fields are signed with a DNS-based key
- Visibility: No, normally not visible to recipients
In summary: In contrast to DKIM, S/MIME certifies not only your domain, but also the personal sender address that you use for a mailing.
S/MIME in EMM
EMM SaaSAGNITAS takes over the installation
In order to make the use of S/MIME in EMM as convenient as possible for you, AGNITAS takes care of the problem-free integration of the feature. If you decide to use S/MIME, our employees will store the certificates you provide for the sender addresses you require.
All mailings from your client sent via these sender addresses are then automatically signed with your certificate for the period of validity. This ensures maximum security and authenticity in your email communication. You do not need to make any further configurations yourself.
EMM InhouseSetup on your servers
If you use EMM Inhouse, you must integrate S/MIME into EMM yourself, as AGNITAS does not have access to your own servers. We will provide you with detailed instructions to ensure that the setup is nevertheless easy and smooth. If you have any questions during the process, we will of course be happy to assist you.
As soon as you have stored your S/MIME certificates, all mailings from your client sent via the selected sender address are automatically signed with your certificate for the period of validity. This ensures maximum security and authenticity in your email communication.