Compriva Private Email & Messages


  • Share securely!
  • Keep content private!
  • Avoid scams, fraud
  • Keep your email address
  • PC, tablet and mobile
  • Free and Pro versions

Tools(certificate login required)

Frequently Asked Questions

  • What is Compriva Private Email?

    Compriva Private Email is a secure email solution that anyone can install and start using in five minutes. It combines industry-standard email encryption with secure messaging from any contact's browser on any device  from both subscribers and non-subscribers*.

    Unlike regular email, Compriva Private Email is not vulnerable to aggressive search and data mining technology or to email hacks and other criminal exploits supporting identity theft and other forms of fraud.

     * US Patent No. 8,549,280

  • How does Compriva Private Email work?

    Compriva Private Email empowers your existing email software to authenticate (digitally sign) and encrypt (employing public key cryptography) any form of digital content sent by email to another Compriva Private Email user, and decrypt emails received from them. As well, Compriva supports browser-based encrypted messaging to other Compriva subscribers and from any trusted contact.

    Authentication ensures that you and your correspondent can both be completely confident that you are dealing with someone you trust, and that the message is received exactly as it was created (has not been tampered with).

    Encryption ensures that no person (except the originator and intended recipient) or machine can read/ has read the message.

  • Why should I subscribe to Compriva Private Email?

    If you are concerned (for personal or business reasons) about the privacy and integrity of your email correspondence, you will want the best protection you can achieve with your existing communications software. Microsoft Windows users running Outlook, Outlook Express, Windows Live Mail, or Windows Mail desktop have the inherent capability to support authentication and strong encryption. Compriva Private Email subscribers can leverage this capability to enjoy digitally signed and/or encrypted email communication with other Compriva Private Email users, and browser-based encrypted messaging to other subscirbers and from any trusted contact.

  • Can I use it Compriva Private Email from other platforms/devices/email client programs?

    Yes! Once properly installed on a supported Windows OS/email client program, your Compriva digital certificates can be easily exported to other OS/email client programs that support S/Mime secure email (e.g. Thunderbird on Mac OS or Linux).

    Furthermore, ComprivaLinks you send to any trusted contact can be opened on any browser (PC, Mac or smartphone) that supports SSL connection to our Compriva secure server. Once connected, your contact can use the presented webform to compose and send you an encrypted ComprivaNote. The webform can be bookmarked and saved with other favourites to be re-used anytime from any device!

  • Why can anyone install and start using Compriva Private Email so quickly?

    Absolutely no technical knowledge or skill is needed! So long as you are sending and receiving email (at the address you want to use for Compriva) from a supported Windows email client program (see list), all you need to do is complete the registration web page (Try or Buy) and the instructions in the subsequent email you will receive. Our sophisticated installer will deliver and install the Compriva digital certificates you require and correctly configure your email client program(s). On completion, follow the simple steps in our Getting Started tutorial to start sending and receiving encrypted emails within minutes.

  • What do I get as a subscriber of Compriva Private Email?

    When you subscribe to and install Compriva Private Email:

    • You will be provided with the Compriva digital certificates you need to sign and/or encrypt your email and attachments to other subscribers and to read encrypted email you receive from them.
    • Your email client programs will be automatically configured* to send and receive digitally signed and/or encrypted email.
    • Using only your browser you can send encrypted ComprivaNotes™ to any Compriva subscriber.
    • You can use the Send ComprivaLink™ tool to empower any trusted contact (including non-subscribers!)** to send you encrypted ComprivaNotes from any browser (PC, Mac, tablet or smartphone)… no log in, registration or installation required!
    • You can use Find a Friend to quickly check if a contact has installed Compriva Private Email and, if so, immediately establish secure email communications with him/her.
    • You can use Invite a Friend to invite contacts who don't have Compriva Private Email to install a free 90-day trial and enjoy private email communications with you.

    Your Compriva Private Email subscription is for unrestricted use (it may be used for any lawful personal and/or business purpose) within its expiry period.

    * non-Microsoft email client programs require manual configuration – instructions available in Compriva Support

    ** US Patent No. 8,549,280

  • Do both sender and recipient have to be Compriva Private Email subscribers?

    For full functionality, both sender and recipient must have Compriva digital certificates (active trial or paid subscriber) installed.

    Any trusted contact (subscriber or not) who has received a ComprivaLink from a subscriber can use it to send an encrypted ComprivaNote to the initiating subscriber.

  • Can I use my existing email software?

    Yes - for Windows users who are using Microsoft email client software on PCs or full OS tablets. Compriva Private Email installs on, works with and leverages the features of Outlook, Windows Live Mail, Windows Mail and Outlook Express using your existing email account. You do not have to manage a second email system or email address.

  • Can I use my existing address book?

    Yes - for most users.  This is another unique feature of Compriva Private Email.  Since Compriva Private Email leverages the features of Microsoft email client programs, it uses your existing address book.

  • How do I know Compriva Private Email is really protecting my email?

    On any encrypted and/or signed message you send or receive, simply look for the icons in the message header similar to those depicted in the following example. Depending on the program in use, the icons could be on either side of the header:

    Outlook Express email window showing signed and encrypted icons.

    The red seal icon indicates a signed message. To inspect the signing certificate, simply click on the icon with your mouse. The resulting pop-up window tells you whether or not the certificate is valid. Click on "View certificate" for full certificate details, including the originator's email address, dates of issue and expiry, etc.

    The blue lock icon tells you that the message is encrypted. To inspect the encryption certificate, simply click on the icon with your mouse. The resulting pop-up window tells you which algorithm was used to encrypt the message. Compriva Private Email supports 3DES, which is an industry standard delivering an effective 168-bit encryption strength. When you choose "View Certificate", you will see the details of your own encryption certificate (whether you have sent or received the message).

    Remember, when you digitally sign a message, the recipient knows it can only be from you and has not been tampered with. When you encrypt a message, only you and the intended recipient can read it.

  • What will my registration information be used for?

    Your name and email address is needed to properly identify you to the people with whom you wish to have protected communications. Additional information is used for credit verification. View our Privacy Policy.

  • How many people can I have private email communications with?

    There is no limit.

    You can send/receive private, secure email to/from any Compriva Private Email subscriber.

    You can send secure, encrypted ComprivaNotes to any Compriva Private Email subscriber.

    You can receive secure encrypted ComprivaNotes from any Compriva Private Email subscriber and from any trusted contacts (subscribers or non-subscribers) to whom you send ComprivaLinks.

  • When and how do I accept another Compriva Private Email user's digital signature?

    Before you can encrypt email to another Compriva Private Email user using your email client program, you must accept that person's digital signature and update your "Contacts" folder (Outlook users) or "Address book" (Outlook Express users). This only needs to be done once (unless either party's Compriva Private Email certificate changes for any valid reason).

    1. Begin by asking your selected correspondent to send you a digitally signed message (for maximum security you should use another communications medium to do this -- never accept a digital signature unless you are completely confident that it belongs to a trusted correspondent).

    2. Open the Compriva Private Email digitally-signed message you just received from your trusted correspondent. (Viewing the message in the "Preview" pane is not sufficient -- make sure you double-click on the email message to open it in a new window.)

      Outlook users:

      Add the certificate to your "Contacts" folder by right-clicking the "From" field and selecting Add to Contacts, then Save and Close. If that contact is already in your "Contacts" folder, a new window "Duplicate Contact Detected" will pop up. Select "Update new information from this contact to the existing one", then OK to close.

      Note to Outlook 2013 users: You may find that Outlook 2013 will not update an existing contact with a new certificate. If that occurs, delete the existing contact and then right-click on the "From" field of the newly-received digitally signed email to save the sender’s information as a new contact (which will include its valid certificate).

      Windows Live Mail Users:

      On receiving a digitally signed message from your contact, right click on the "From" field and select "Add to Contacts" or "Edit Contact". On the left hand side of the pop-up window, select "IDs" to see details of the certificates associated with that contact. The most recent valid certificate should have a green check mark and be labelled as "Default". If not, select it and click on "Set as preferred certificate", then "Save".

      Outlook Express users:

      If this is the first digital signature you have accepted for this contact, simply select "Reply" and compose and send a reply. Outlook Express will automatically add the contact to your address book with its certificate.

      If this is a message from an existing contact with a new or updated certificate, you will need to update the sender's certificate in your Address Book by scrolling to and right-clicking on the sender's address. Select Properties from the dropdown list, then choose the tab "Digital IDs". Select the newest valid certificate (it will have a green check mark), then click on the "Set as Default" button and click OK to close.

    3. Now close your Address Book/Contacts folder. Since the received message is still open, you can now select the Reply button on that message and both sign and encrypt the reply.

    Special notes!

    It is a good idea to delete duplicate contacts (same email address). Be sure to retain the contact with the valid Compriva Private Email certificate.

  • Once a contact has a Compriva Private Email certificate, how do I digitally sign a message to that person?

    Open your new message window and address and compose your message as usual. Be sure to select the email address for which your contact has installed a Compriva Private Email certificate. Use the "Sign" icon on the toolbar of your new message window to sign the message before you send it. Be sure to send your signed message using the email account for which you have installed your Compriva Private Email certificate.

  • Once a contact has a Compriva Private Email certificate, how do I encrypt a message to that person?

    Before you encrypt a message to another Compriva Private Email user for the first time, you must receive a digitally-signed message from that person and accept his/her digital signature. This does not need to be done again until that user installs another Compriva Private Email certificate.

    Open your new message window and address and compose your message as usual. Be sure to select the email address for which you accepted your contact's Compriva Private Email digital signature. Use the "Encrypt" icon on the toolbar of your new message window to encrypt the message before you send it. Be sure to send your encrypted message using the email account for which you have installed your Compriva Private Email certificate.

  • Where do I find the "Sign" and "Encrypt" icons in my email client?

    The "Sign" and "Encrypt" icons appear as two envelopes on your email client's toolbar when you are composing a new message or replying to or forwarding an existing message -- one icon has a blue lock on it; the other a red seal.

    Outlook 2013:

    The icons appear under the "Options" tab in the "New Message" window: Outlook 2013 options tab showing sign and encrypt icons.

    Outlook 2007:

    The icons appear in "New message" tab in the "Options" section as depicted in the following image: Outlook 2007 toolbar showing sign and encrypt icons.

    Earlier versions of Outlook:

    The icons typically appear towards the right-hand side of the toolbar as depicted in the following image:

    Earlier Outlook toolbar showing sign and encrypt icons.

    Windows Live Mail:

    The icons can be found under the "Options" tab in the "New Message" window as shown here: Windows Live Mail toolbar showing sign and encrypt icons.

    Outlook Express:

    The icons typically appear as depicted in the following image:

    Outlook Express toolbar showing sign and encrypt icons.

    If you use Outlook and do not see these icons, please go to I don't see any icons for signing and encrypting.

  • How can I set up Compriva Private Email amongst a group of selected correspondents?
    1. Confirm the names and email addresses of all designated group members in your Outlook Express address book or Outlook Contacts folder.
    2. Ensure that each member has a correctly installed Compriva Private Email certificate (you can use Invite a Friend or ask them to obtain their own).
    3. Advise each member of names and email addresses of all group members with installed Compriva Private Email certificates.
    4. Instruct each member to exchange digitally signed messages with every other group member. Outlook users must update Contacts folder on receipt of each digitally signed message.

    On completion, every group member can exchange encrypted email with every other group member.

  • Why do I need a "shared secret"?

    You may know a "John Doe" with an email address that you recognize. If you receive a digitally signed message that appears to be from that person, you will want to confirm that before accepting that signature and updating your Contacts folder/address book. This is because there is a possibility that an unknown party is using the name "John Doe", has obtained unauthorized access to John Doe's email servers and has misrepresented him/herself to obtain a Compriva Private Email certificate. If you and John Doe communicate by some independent means (i.e. Phone or FAX) and agree on a "shared secret" to be included with your initial exchange of digitally signed messages, you can each be confident that the digital signature on the message you receive is that of the party you know and trust. Once you accept each other's signed messages and update your respective Contacts folders/address books, you can be sure that messages and attachments that you sign and encrypt to each other will not be seen or tampered with by any unauthorized person or machine.

  • Do I have to invite a person with every signed or encrypted email message I send to him/her?

    No. You only need to invite a person if they have not yet installed a valid Compriva Private Email certificate, which can be a free trial or a purchased subscription. So long as both you and your correspondent maintain valid Compriva Private Email digital certificates (and you have each correctly updated your Contacts folders/address books), you can sign and encrypt to each other at will.

  • Can two people I have sent Compriva Private Email certificates to communicate with private email?

    Yes, provided you have followed the instructions to include them in a group.

  • How long is the Compriva Private Email certificate good for?

    Your Compriva Private Email certificates with which you sign and decrypt messages are valid for the duration of your paid subscription up to a maximum of two years from your subscription (registration) date. A standard one-year paid subscription may be renewed for an additional year at any time -- any remaining time on the current subscription will be added to the duration of the renewed subscription. Trial Compriva Private Email certificates are valid for 90 days from your trial registration date.


    Do not delete expired digital certificates from your machine. You will need them in order to decrypt (read) any messages that were encrypted with them.

  • Is there any limit to the number of private emails I can send or receive?

    No. As long as both you and your correspondents have valid Compriva Private Email digital certificates, you can send and receive as many private, secure emails as you like between yourselves.

  • What happens when my subscription to Compriva Private Email expires?

    About a month before your subscription expires, you will receive an email from us advising you of the expiry date and inviting you to renew your subscription.

  • When my Compriva Private Email certificate expires, do I have to pay again?

    Yes. Compriva Private Email is an actively managed service that enables you to protect email correspondence -- not unlike paying for anti-virus software.

  • What happens if I don't renew my Compriva Private Email subscription?

    You will not be able to digitally-sign new messages. Other Compriva Private Email users will not be able to encrypt messages to you because the certificate they have in their contacts folders/address books for you will have expired.

  • When I renew my subscription and install a new Compriva Private Email certificate, do I need to notify my Compriva Private Email contacts?

    Yes. After you have installed a new Compriva Private Email certificate for any reason, you need to send digitally-signed messages to your Compriva Private Email contacts so that they can update their address books/contacts folders. It's a good idea to include a previously agreed upon shared secret in the message for extra security.

  • Are documents I attach to the email private as well?

    Yes. All documents sent as attachments to an encrypted email are encrypted as well so that only the intended recipient can open and read them. The recipient must of course take measures to protect access to his/her computer, passwords and digital certificates.

  • Other questions?

    Have you checked our Troubleshooting Tips page. You may find the answers you're looking for there.

    If you still can't find what you're looking for, please visit our Support Request Form and send us your questions and we'll try to answer your questions as best we can.

Authenticated, Encrypted, Private Email