I am getting the initial exception again:

Hey. Are there any new regarding this ticket?

I'll look into it.

Ok, I will reload the mail item then!

Thank you! The beta38 is working for me. Guess the mail->setPassWrite (true); line from the last commit did the trick. I did not need to reload the mail object again.

I tested these window messages with the provided beta build. Both messages gets processed and the e-mail is encrypted again but I still receive the 0x80004004 (E_ABORT) error when trying to save the message via the outlook api.

Ok. Thank you for sharing informations!

So maybe closing the inspector, too is necessary here so that the real close / unload on the mail is triggered. But it might just be that Outlook immediately reopens the mail in your case. Then it won't help but I think you should try that, too because any Interprocess communication will be more effort.

Yes that is expected, we block the save event as long as we have replaced the Body / Attachments of the mail with decrypted contents are shown. In our debug log you would see the message "Canceling write event".

Yes, I can confirm that log entry.