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Microsoft Office Outlook Edition

Microsoft Office Outlook Edition

2018/06/25

Revision History 

Rev.

Date (YYYY/MM/DD)

Description

Editor

V.1.0

2015/4/1

First revision

NII

V.1.1

2016/12/26

Amendment with addition of [NII Open Domain S/MIME CA] as a new Certificate Authority

NII

V2.0

2018/2/26

Supported environment update: Outlook 2013 or later

NII

Table of Content

1. Installing the S/MIME Certificate
1-1. Operating Environment
1-2. Prerequisites
1-3. Install Procedure
2. Sending Digitally Signed E-mails
2-1. How to Send Digitally Signed E-mails
2-2. How to Confirm a Sent E-mail That Was Digitally Signed

 

1. Installing the S/MIME Certificate

1-1. Operating Environment

The procedures only in the following environment are described in this document:

Supported environment:

Microsoft Office Outlook 2013 or later

 

1-2. Prerequisites

The prerequisites for using the S/MIME Certificate in Microsoft Office Outlook are described.
Replace the technical terms according to the user environment in which the S/MIME Certificate will be used. (The procedures required for Microsoft Office Outlook 2013 are described in this document.)

Prerequisites

  1. The S/MIME Certificate has been installed in the web browser
    (described in the User's Manuals for Installation in Different Web Browsers: Microsoft Internet Explorer Edition); and

  2. Microsoft Office Outlook 2013 or later is installed.

 

1-3. Install Procedure

Installing the Certificate

  1. Open Microsoft Office Outlook and click on the [File] tab.



  2. Click [Options] in the menu list on the left side of the [Account Information] screen.
     


     

  3. In the [Outlook Options] dialog box, select [Trust Center] in the list of options on the left side of the dialog box and then click [Trust Center Settings...].


     

  4. In the [Trust Center] dialog box, select [E-mail Security] in the list of options on the left side.
    Check the [Add digital signature to outgoing messages (D)] and [Send clear text signed message when sending signed messages (T)] checkboxes and click [Settings...(S)].



  5. The [Change Security Settings] dialog box will appear. Enter any string in the [Security Settings Name:] box.
    Check both [Default Security Setting for this cryptographic message format (T)] and [Default Security Setting for all cryptographic messages (M)] checkboxes,
    and then click [Choose...(C)] for the [Signing Certificate].


     

  6. In the [Windows Security] dialog box, select the S/MIME Certificate and click [OK].


     

  7. Select [SHA256] from the [Hash Algorithm (A):] drop down list and [3DES] from the [Encryption Algorithm (L):] drop down list. Check the [Send these certificates with signed messages (E)] checkbox and click [OK].



     Note: Select a relevant Hash Algorithm for the user environment.

  8. Click [OK].
     


     

  9. Click [OK].



     This completes the S/MIME Certificate installation.