Note this guide assumes you have already installed a Secure Email (S/MIME) certificate.
For guides related to S/MIME installation, please consult our article here.
Select your email client from the list below for your guide:
Microsoft Outlook 2016
Microsoft Outlook 2013
Mozilla Thunderbird
Apple Mail
Microsoft Outlook 2016
To Sign an Email Message, simply click the Sign button that now appears on a Compose Message email dialogue under the Options tab.
When users receive your email, they will see a message that the email has been digitally signed.
However, note to exchange secure (encrypted) emails with someone, there are some additional steps required.
To Encrypt an email Message, you will need to provide your public key to the party you wish to encrypt for, and vice versa.
The recommended way to do this exchange is to send the other party a Signed email to exchange keys
1. Open a new message to send to the contact with whom you wish to exchange public keys. Ensure the message is digitally signed (but not encrypted) and hit send. You will be prompted to Allow for your public key to be sent upon sending the email. Select Allow.
2. You will need a copy of the recipient's public key to exchange Encrypted email. Have them send you a digitally signed email. After receiving the digitally signed email containing a copy of the other person's public key, Outlook will store the public key. Upon opening the email you will be prompted again. Select Allow to obtain a copy of the public key being sent to you.
3. You can make sure the recipients 's certificate and public key have been stored by clicking on Certificates in their contact profile. Add the contact by opening their email, right-clicking on their name and selecting "Add to Outlook Contacts".
4. Click Save and Close.
| You can now exchange encrypted emails with that user. |
Microsoft Outlook 2013
To Sign an Email Message, simply click the Sign button that now appears on a Compose Message email dialogue. There is no other setup required.
When users receive your email, they will see a message that the email has been digitally signed.
However, note to exchange secure (encrypted) emails with someone, there are some additional steps required.
To Encrypt an email Message, you will need to provide your public key to the party you wish to encrypt for, and vice versa.
The recommended way to do this exchange is to send the other party a Signed email to exchange keys
1. Open a new message to send to the contact with whom you wish to exchange public keys. Ensure the message is digitally signed (but not encrypted) and hit send. You will be prompted to Allow for your public key to be sent upon sending the email. Select Allow.
2. You will need a copy of the recipient's public key to exchange Encrypted email. Have them send you a digitally signed email. After receiving the digitally signed email containing a copy of the other person's public key, Outlook will store the public key. Upon opening the email you will be prompted again. Select Allow to obtain a copy of the public key being sent to you.
3. You can make sure the recipients 's certificate and public key have been stored by clicking on Certificates in their contact profile.
4. Click Save and Close.
![User-added image]()
Mozilla Thunderbird
![User-added image]()
A new icon, Security, will now appear in your Write message window. You can Encrypt or Digitally Sign messages by selecting either or both options.
Mail sent with a digital signature will show as digitally signed by the sender to any receiver of that email.
To be able to send and receive encrypted email with someone else, note there are some additional steps to complete.
1. Send a signed email to a recipient. Make sure that person stores your profile so that they can retain your public key.
2. You will also need a copy of that person's public key. Have them email you a digitally signed email.
3. You will receive the digitally signed email as below. Digitally signed email will appear with the icon outlined in red below.
![User-added image]()
4. To ensure you have received the sender's public key, got Account Settings > Security > View Certificates. Go to the People tab to confirm the sender's certificate has been stored.
![User-added image]()
![User-added image]()
Apple Mail
1. Open a new message. Note two new icons will be available: (1) a small lock icon (2) a digital signature icon.
![User-added image]()
2. You can send a digitally signed email by having the digital signature option turned on. The recipient will receive the message as a digitally signed email.
To send Encrypted email there are some additional steps required to allow the recipient to decrypt the email.
You must exchange public keys with a user in order to exchange Encrypted email. To do so send the user a digitally signed email and have them respond to you with a digitally signed email. Upon receiving the digitally signed email, add the user's contact by finding the update button on the right side of the message header.
![User-added image]()
You can now send that user an Encrypted email and they will be able to view its contents.
![User-added image]()
You can confirm you have added the user's certificate by checking Keychain Access and seeing their certificate listed there.
If you have any questions or concerns please contact the Entrust Certificate Services Support department for further assistance:
Hours of Operation:
Sunday 8:00 PM ET to Friday 8:00 PM ET
North America (toll free): 1-866-267-9297
Outside North America: 1-613-270-2680 (or see the list below)
NOTE: It is very important that international callers dial the UITF format exactly as indicated. Do not dial an extra "1" before the "800" or your call will not be accepted as an UITF toll free call.
The recommended way to do this exchange is to send the other party a Signed email to exchange keys
1. Open a new message to send to the contact with whom you wish to exchange public keys. Ensure the message is digitally signed (but not encrypted) and hit send. You will be prompted to Allow for your public key to be sent upon sending the email. Select Allow.
2. You will need a copy of the recipient's public key to exchange Encrypted email. Have them send you a digitally signed email. After receiving the digitally signed email containing a copy of the other person's public key, Outlook will store the public key. Upon opening the email you will be prompted again. Select Allow to obtain a copy of the public key being sent to you.
3. You can make sure the recipients 's certificate and public key have been stored by clicking on Certificates in their contact profile.
4. Click Save and Close.
| You can now exchange encrypted emails with that user. |
Mozilla Thunderbird
A new icon, Security, will now appear in your Write message window. You can Encrypt or Digitally Sign messages by selecting either or both options.
Mail sent with a digital signature will show as digitally signed by the sender to any receiver of that email.
To be able to send and receive encrypted email with someone else, note there are some additional steps to complete.
1. Send a signed email to a recipient. Make sure that person stores your profile so that they can retain your public key.
2. You will also need a copy of that person's public key. Have them email you a digitally signed email.
3. You will receive the digitally signed email as below. Digitally signed email will appear with the icon outlined in red below.
4. To ensure you have received the sender's public key, got Account Settings > Security > View Certificates. Go to the People tab to confirm the sender's certificate has been stored.
| You can now exchange encrypted emails with that user. |
Apple Mail
1. Open a new message. Note two new icons will be available: (1) a small lock icon (2) a digital signature icon.
2. You can send a digitally signed email by having the digital signature option turned on. The recipient will receive the message as a digitally signed email.
To send Encrypted email there are some additional steps required to allow the recipient to decrypt the email.
You must exchange public keys with a user in order to exchange Encrypted email. To do so send the user a digitally signed email and have them respond to you with a digitally signed email. Upon receiving the digitally signed email, add the user's contact by finding the update button on the right side of the message header.
You can now send that user an Encrypted email and they will be able to view its contents.
You can confirm you have added the user's certificate by checking Keychain Access and seeing their certificate listed there.
| You can now exchange encrypted emails with that user. |
If you have any questions or concerns please contact the Entrust Certificate Services Support department for further assistance:
Hours of Operation:
Sunday 8:00 PM ET to Friday 8:00 PM ET
North America (toll free): 1-866-267-9297
Outside North America: 1-613-270-2680 (or see the list below)
NOTE: It is very important that international callers dial the UITF format exactly as indicated. Do not dial an extra "1" before the "800" or your call will not be accepted as an UITF toll free call.
| Country | Number |
| Australia | 0011 - 800-3687-7863 1-800-767-513 |
| Austria | 00 - 800-3687-7863 |
| Belgium | 00 - 800-3687-7863 |
| Denmark | 00 - 800-3687-7863 |
| Finland | 990 - 800-3687-7863 (Telecom Finland) 00 - 800-3687-7863 (Finnet) |
| France | 00 - 800-3687-7863 |
| Germany | 00 - 800-3687-7863 |
| Hong Kong | 001 - 800-3687-7863 (Voice) 002 - 800-3687-7863 (Fax) |
| Ireland | 00 - 800-3687-7863 |
| Israel | 014 - 800-3687-7863 |
| Italy | 00 - 800-3687-7863 |
| Japan | 001 - 800-3687-7863 (KDD) 004 - 800-3687-7863 (ITJ) 0061 - 800-3687-7863 (IDC) |
| Korea | 001 - 800-3687-7863 (Korea Telecom) 002 - 800-3687-7863 (Dacom) |
| Malaysia | 00 - 800-3687-7863 |
| Netherlands | 00 - 800-3687-7863 |
| New Zealand | 00 - 800-3687-7863 0800-4413101 |
| Norway | 00 - 800-3687-7863 |
| Singapore | 001 - 800-3687-7863 |
| Spain | 00 - 800-3687-7863 |
| Sweden | 00 - 800-3687-7863 (Telia) 00 - 800-3687-7863 (Tele2) |
| Switzerland | 00 - 800-3687-7863 |
| Taiwan | 00 - 800-3687-7863 |
| United Kingdom | 00 - 800-3687-7863 0800 121 6078 +44 (0) 118 953 3088 |
