I doubt this is simple to do. Thunderbird does not expose an API to send emails.

Does this discussion offer anything useful?

http://www.vbforums.com/showthread.php?860467-RESOLVED-Accessing-Thunderbird-functions

Solution is based on MAPI , Old VB6 - which has become obsolete. Further they create problems in windows 64 bit system

We are looking for .net component to send mail to thunderbird or the function by which we can create thunderbird object in .net windows application

Suresh Bansal

MAPI is still supported, that you do not wish to use it for whatever reason is not something we can help you with.

I think you also best ask Microsoft why they include mapi in their Visual Studio 2017 documentation. https://docs.microsoft.com/en-us/cpp/mfc/mapi?view=vs-2017 No mention of it being deprecated in Visual Studio or anywhere else.

Thunderbird also has a 64bit mapi DLL that handles much of the issues associated with MAPI on 64bit systems.

Your only other choice is the SendTo protocol which Thunderbird supports. But it offers no way to click send so spamming with it is very difficult.

Thanks for reply

But we don't want to follow MAPI route due to following

a) 32 bit , 64 bit windows issuses

b) MAPI sends to default mail client which may or may not be there.

We wish to provide multiple mail clients lke outlook, mail, smtp, thunderbird etc. - user wise - without any intervention by user - total handling by .net windows application

Suresh Bansal

Perhaps you need to reconsider your approach. If you are going to go to the trouble of building a mime handler to use SMTP just use it and forget the mail clients entirely. IF they use Outlook.com or Gmail derived SMTP server their IMAP sent folders will be updated automatically by the SMTP action.

Hi

Thunderbird is popular email client ->I wonder there is no .Net component developed by Mozilla or 3rd Party vendors to send mails to it ->which is independent of 32 bit /64 Bit systems as majority of .Net components are.

Suresh Bansal