Trouble signing emails

Jan 25, 2011 at 10:01 AM
Edited Jan 25, 2011 at 10:02 AM


I followed this post in and tried to use this package to sign email messages.  The results have been a bit dissappointing to me.  I succeeded in signing plain text emails, but these issues arised:

1.- Signed emails could not be verified by email client.  When a plain text email is signed and sent, the email client needs to manually install the certificate.  I've checked that, if you send a signed email from Thunderbird, if another Thunderbird client receives the email, it appears as signed and correct, even if the recipient has no CA certificate installed.  This doesn't happen when I send a signed email using MailSystem.NET.  Is there a way to do that?  Could some sample code be provided in order to achieve that?

2.- Emails containing images are not signed correctly.  We create HTML emails, with embedded images in it.  We sign them too.  But, in this case, email clientes say that signature is wrong.  Is it possible to do this?  If so, how can that be done?

Please let me know if you need some source code to check what's going on.

Thanks a million in advance, any contributions would be greatly appreciated.