Windows Mail recipient problem


I have successfully installed my Secure Email Certificate on a Windows XP, Outlook 2002, system. I have sent a ‘digitally signed’ email to a client address. The client has Windows Vista with Windows Mail program. They have opened the email, which clearly tells them it has been digitally signed.

Following the published instructions they have right-clicked on the sender’s address and saved it to their ‘Contacts’ list, as well as saving it to their ‘Trusted Senders’. The Public Key shows up within their mail program under:
Windows Mail>Tools>Options>Security>Digital IDs>Other People.

The problem is that they are unable to digitally sign or digitally encrypt either a reply, or a new email sent to the sender’s address. When trying to do so, a message comes up saying that to do it they need to apply for their own digital certificate.

Is this a problem specific to Windows Mail or am I missing something?

A ‘worried bunny’

My thanks are to Jonathan at Comodo Support for the answer to the problem. It seems to me the guidance in the Knowledgebase is misleading. Here is his take (slightly adjusted!) on how secure email certificates work:

  1. Request a Certificate at
  2. On Receiving the Certificate please install as per the instructions accompanying it.
  3. First send an email to the recipient digitally signed, who should open it, highlight your address by right clicking it and then save it to ‘Contacts’.
  4. Ask your recipient to then reply to the same email so that you can be sure that the recipient has your public key.
  5. Now you can send an encrypted mail to the recipient.

The recipient need your public key to view (decrypt) the encrypted email which was sent by you.

Note: The recipient needs his OWN certificate for his email address to be able to send encrypted email to you.

Hopefully this will help those of us who have been having s problem with setting the system up amongst our email contacts.


If you still have a problem, you can also submit the ticket in the following link