Mailsecurity S/MIME

Information about the Securepoint Mailsecurity Product S/MIME

Last adaption: 04.2026

New:

(2026.01)
(2025.12)

notempty

This article refers to a Beta version

-

General

S/MIME stands for Secure/Multipurpose Internet Mail Extensions and is a standard that enables emails to be processed and signed using asymmetric encryption. With S/MIME, it is ensured that emails are confidental, authentic, and unaltered. S/MIME can be booked in combination with Securepoint Mail Security through the reseller portal see booking information ensuring secure email communication Further questions and answers about S/MIME can be found in the Mailsecurity FAQ.

Prerequisite

A mailbox must be created in an incoming route.

When using the Office 365 integration, this is done as part of the assistant.
For manually created routes, mailboxes must also be created manually:
- Go to mail.security Incoming in the Routes (x) tab, and click the n button in the Mailboxes column for the desired domain/route
  Datei:MaS Create Mailboxes Routes.png
- Click the Add New Mailbox button
- Fill out the Add New Mailbox dialog
  Set the username, domain, and frequency of the spam report
  Datei:MaS v1.2 Mailsecurity Incoming Add Mailbox.png
- Add the mailbox by clicking the Add button

Now, S/MIME can be set up for the mailbox.

More information in the Guide to Creating Mailboxes.

Setup

The setup of S/MIME is done in the Mail Security Portal under mail.security S/MIME S/MIME .

Before proceeding, an initial setup of Mail Security and the creation of an inbound route and, if necessary, an outbound route must be completed beforehand.

Caption	Value	Description	Menu item S/MIME
Mailboxes		Number of created mailboxes
Licenses		Number of booked S/MIME licences
Active		Number of active S/MIME licences

notempty New		Refreshes the display
Activate		If multiple inactive mailboxes are selected using a checkbox , S/MIME can be enabled for them in bulk
Deactivate		If multiple inactive mailboxes are selected using a checkbox , S/MIME can be enabled for them collectively
The table shows created mailboxes under mail.security Inbound (Instructions for creation)
Certificate ID only when active	123456	ID of the S/MIME licenses
Mailbox	test2	Name of the Mailbox
Domain	mx.ttt-point.de	Domain of the mailbox
S/MIME	Active	S/MIME status (inactive/ activating/ active)
Actions	Activate only when inactive	Activates S/MIME for the respective mailbox, alternatively, multiple mailboxes can be selected using the checkboxes and collectively activated via the Activate button above the table.
	Upload only when inactive	Activates S/MIME with an uploaded certificate
	Deactivate only when active	Deactivate S/MIME for the particular Mailbox. Alternatively, multiple mailboxes can be selected using the checkboxes and collectively deactivated via deactivate in the table.
	Save	Mail Security certificates of your own mailboxes can be downloaded for distribution

Encryption

notempty

New as of 04.2026

Caption

Value

Description

Overview of Encryption Rules

Priority

2

Rules are prioritized, where 1 has the highest priority. New rules are created with the highest priority.

The priority can be adjusted using the arrows next to the encryption rule.

Actions

Edit Encryption rule

Delete encryption Rule

Managed Mailbox/Domain

ttt-point.de

A mailbox managed by Securepoint mail.security within this organization.

External Mailbox/Domain

ttt-point.de

A mailbox outside of this organization, to which emails are sent or received.

Incoming

Always decrypt Encrypted emails

Rules for incoming emails

Starting from

Sign only

Rules for outgoing emails

notempty

New as of 04.2026

Create new Rule

Managed Mailbox/Domain

ttt-point.deAny

A mailbox managed by Securepoint mail.security within this organization.
A maximum of 20 entries can be selected, seperated by commas. Or all entries with All.

Create new Encryption Rule

External Mailbox/Domain

anyAny

A mailbox outside of this organization, to which emails are sent or received.
A maximum of 20 entries can be selected, seperated by commas. Or all entries with All.

Incoming

Always decrypt Encrypted emails

Rules for incoming emails

Not defined	No changes are made to rules with lower priority, default settings are used if applicable.
Do not Decrypt	Encrypted emails are accepted and delivered encrypted.
Optional decrypt	Encrypted emails are decrypted when possible (DEFAULT). Emails that cannot be decrypted are delivered encrypted
Always decrypt Encrypted emails	Unencrypted emails are accepted. If an encrypted email cannot be decrypted, the sender receives an error report.
Force Decryption	Only encrypted emails are accepted. Unencrypted emails are rejected, and the sender receives an error report

Starting from

Sign only

Rules for outgoing emails

Not defined	No changes are made to rules with lower priority, default settings are used if applicable.
Neither sign nor encrypt	Emails are sent unsigned and unencrypted (DEFAULT).
Sign only	Emails are sent signed and unencrypted (DEFAULT, certifikate set up for signing).
Encrypt optional	Emails are signed and encrypted if possible.
Enforce Encryption	Emails are exclusivley sent signed and encrypted. If this is not possilbe, the sender receives an error report.

Add Pubkey

mail.security S/MIME Public Keys To encrypt an email, a public key for the recipient must be available via a signed incoming email. If this is not the case, it can be imported manually using the button at the bottom right. notempty Only mailbox certificates can be imported. Domain certificates cannot be imported!
Caption	Value	Description	Pubkey Overview
Action	Delete	Deleting the certificate
Certificate key	123456	Unique key for this certificate
Valid from	2023-12-31T23:00:00+01:00	Date of certificate creation
Valid to	2037-12-31T22:59:59+01:00	Certificate expiration date
Import date	2025-04-10T15:14:00+02:00	Import date
Mailbox	maria@ttt-point.de	Mailbox to which the certificate belongs
Aliases
Source	manual	Source of the certificate