smime C# encrypted emails with attchments

Question

I need to send encrypted emails using C# without using any third party component. This is pretty much working as long as I do not need attchments on the email but as soon as I add attchments, I face the same problem as described on http://social.msdn.microsoft.com/forums/en-US/netfxnetcom/thread/74e4711e-1f66-43a7-9e3b-bc9cfbcd1b73/

There is a solution posted here which is using attchment.rawdata and attachment.filename which is some onject I know nothing about. What can be rawdata?

Answer 1

See the constructors for the Attachment class.

If you pass in a Stream you can pretty much put anything in the attachment.

Answer 2

Have a look a http://istern.dk he has just posted a series of post on howto do this. His articles shows howto send an email with attachment encrypted and signed. From the beginning on howto create certificates installing them and so on pretty nice articles. small site but with interresting stuff link to part one