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Quick Guide to Install Email Certificate in Microsoft Outlook

Step-by-Step Instructions to Install Email Certificate in Microsoft Outlook

In today’s evolving generation, security threats are at its peak, and people are aware of it. Cyber threats are not new anymore. Malware, ransomware, harmful viruses are not new to any organization as well as a regular internet user. These days, the question isn’t about how to stop it, but in reality, it’s about how to identify and stop being the victim of it.

These dreadful cyber-attacks happen in various ways, and one of the most common ways used by cyber crooks is through email messages. Yes, several harmful spam messages are sent, which are very hard to detect.

So, it’s quite obvious how to combat such threats. How to stop being a victim of such online threats? Well, one sure way answer is to stay updated by reading articles, blogs, and news and have enough knowledge to identify and not click any unknown link you receive through emails, not to open emails sent from unknowns. But, there’s one more way as well, especially when you’re an organization that has to deal with several email messages daily—for example, having a secure email signing certificate installed (also called as an Outlook email encryption certificate or S/MIME certificate).

It can help your organization with the security features provided that prevent phishing while helping you build a trusted network within your organization, so the recipient of an email can get an acknowledgment that the email message is from a trusted source.

But, before we get into details, let’s understand what Email certificate is and why you must have one.

What’s Email Certificate & Reason to Have One

Have you heard about SSL/TLS Certificate? This email certificate works quite similar to it. S/MIME protocol that’s offered through email certificates helps in implementing public and private encryption keys within the delivery process of an email, which encrypts your email before sending it, and it’s called as data at rest encryption. It converts your plaintext email message into an unreadable format so it cannot be read until it’s decrypted by your intended recipient by using its private key.

Moreover, if an email certificate used in Outlook, it also verifies your identification while encrypting the message you’re about to send. Also, the verified user will come across as trustworthy instead of someone who’s sending an email in plaintext.

As you know, what an email certificate is and why it’s so useful, let’s understand some of the vital things you’ll need before you start installing it.

Information Needed for Getting Your Email Certificate

The certificate issuance process of email certificate is quite similar to a code signing certificate, Mozilla Firefox is needed. So, be sure that you’ve got the latest version installed on your computer.

Some of the information needed before starting the installation process of a new email certificate is:

1. Details of the Organization

Once you purchased an email certificate from the respected certificate authority like Sectigo, you’ll have to generate your certificate, and for that, details regarding your organization will be needed, for instance, its name and location.

2. Latest Version of Mozilla Firefox for Generating Email Certificate

Once you fill out all the asked details about your organization, two emails will be sent on your registered email address – one with an email certificate generation link and another with a hash code.

Now, for generating your purchased email certificate, you’ll need to click on that given link, open it in Mozilla Firefox and then paste that received hash code into the text box. Once it’s done, your email certificate will be stored within your web browser.

3. Exporting Generated Email Certificate

  • Once your email certificate is generated, it’ll be stored within your web browser.
  • Now, you’ll have to export it.
  • For that, go to Options, select Privacy and Security.
  • Go to the Certificates tab and click on View Certificates option.
  • From there, select your email certificate and click Backup All and then OK button.
  • It’ll open a pop-up where you’ll be asked to provide the path where you want to save your email certificate.

Here’s How to Install Email Certificate on Outlook

Once the above steps are completed, open Microsoft Outlook and go to File and click on Options
It’ll open Outlook Options. From there, navigate to Microsoft Outlook Trust Center and then select Trust Center Settings.
From the Trust Center window, go to the tab named Email Security, and under that pane, under the Digital IDs (Certificates) tab, click on Import/Export option.
On clicking upon Import/Export option, Import/Export Digital ID window will open, from that select the option, Import existing Digital ID from a file.
Now, click on the Browse button and locate the path where you saved your email certificate and click on the Open button. Now, the file path should fill in the field: Import File.
Now enter your password, which you used while downloading the file and then click on the OK button.
Once you click OK button, Importing a new private exchange key dialog box will appear, then again click OK button.
Select Settings from the Email Security option.
Enter your preferred name for the security settings, once the Change Security Settings windows open.
Once you click on the OK button, the below window will show up. Click on OK.
Your list may differ from this, but steps will remain the same.

  • Also, if you see the option More choices, like above, it simply means you’ve more than one certificate.
  • For selecting a specific certificate, you’ve to click on that More choices option and select the one you want and then press OK.
  • Once the above steps are completed, in the Trust Center window, under section Certificates and Algorithms, click on the Choose button of Signing Certificate field and load the certificate and then click the OK button for confirming the certificate window.
  • Now, repeat for the field Encryption Certificate field. Also, if you’ve more than one certificate, this time, select the same email certificate that you selected in the previous step.
  • Now, click OK button and once the Change Security Settings window is closed, keep the default option selected under the Encrypted email tab.
Once the above steps are completed and you click OK button, your certificate will be installed, and it’ll be ready for signing your email message.

Steps to Sign Your Email Through Your Newly Installed Outlook Email Certificate

It could be possible that you may have successfully installed your email certificate. But, you might not know how to sign your mails using that certificate. For that follow below steps:
  • Before you send an email, go to the Options tab and select the Sign option.
  • If you want, you can also encrypt your email message by simply clicking on the Encrypt button and selecting the option Encrypt with S/MIME.

Once you complete the above steps, all your email messages will be sent in a secure and encrypted format.


Having your email signed using an email certificate is not a compulsion. But, in today’s generation, cyber threats shouldn’t be taken lightly as one wrong step can lead to a massive loss. For protecting yourself from cybercrimes, it’s always suggested to have a proper security protocol within the industry, and having an encrypted email message is one among them, which can be achieved using email certificate offered by trusted certificate authorities like Digicert.

However, if you don’t know how to install or how to sign your email, it’s suggested you go through this quick guide on how to install an email certificate and send your mails securely.

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