You are running in a codepath that means "Outlook told us this was S/MIME, but we have not seen the proper message headers and neither does the data look like it is S/MIME."
Sadly your log does not help much in that case because it marked the mail as bad and aborts.
I've changed that "marking a mail as bad" so that future logs will be more helpful and that it will still try to treat this case as "encrypted" maybe that will already work, although I doubt it. The log will at least be a bit more helpful.

... that would be useful in many ways. I'd say we should support anyone who wants to use pythong-gnupg on windows.

@werner it is like @aheinecke writes:

As I see it Bernhard is just asking for the flat strucuture so basically some export script that creates the needed files on windows.

If they really want to do that for Windows, they can use some database approach like Protonmail does it. This does not require any file structure.

Sorry, we won't implement a server for WIndows. No sane provider uses Windows for a large mail setup.

additional info: I have their certificate(s) and sending encrypted mails to them is successful.

I forgot the debug log:

Gets reported multiple times and should be fixed for the next Gpg4win release as it is a bad first impression. (Although it can convert users to Kleopatra ;-) )

not yet, I try to get to it this week.

i'd be happy to help you set up your own x86 32-bit guest VM for testing
if you like, even if you're running on x86_64 hardware. they're cheap
and easy to run, and have a delightfully small memory footprint :P just
let me know!

I'll look into it.

BTW I am aware that Git repository does not contain many files which are prebuilt in tarballs. I am okay with that, I know the difference. I am just reporting that pinentry's configure script is missing an option, which is clearly needed and which is present in other components.

I wasn't using tarballs. I have fetched code from Git (git clone git://git.gnupg.org/pinentry).

Well, that is a detailed bug report. Thanks.

I'm closing this issues as "Invalid" because it is not an issue of Gpg4win. You can still comment and discuss here.

Ok. If you can confirm that then it means that my analysis is right. Still unexpected to get an error there. I have to do some more tests with Exchange Online but that would be another issue. If this issue is fixed by turning of debugging then it will also be fixed by my patches.

You are right that Outlook behaves normally if debugging is deactivated.
I had major problems with 3.1.4 and never used it until 3.1.5 came
along, so I guess it might be an existing problem.

While I can't reproduce it myself (because I probably don't have the right mails in my exchange) looking at your log I think that I see the problem there might be an issue with the error handling in openProperty. So for old mails the openProperty probably fails because we have exchange online for that and the property is not yet available in Outlook and then the error is not correctly handled and it crashes.

This should be fixed in commit fd34415bdd57332424bd5a98d279e2331678a2fb

3.1.5 was released on 13.11.2018

Was released with 3.1.5

Was released with 3.1.5

3.1.5 is released with this change.

This should work with Gpg4win-3.1.5

hm, adding: --with-tar=tar to my invocation of ./configure appears to leave gpg-zip with:

My problem isn´t linked to forwarding encrypted e-mails and / or attachments. It occurs by ordinary PGP mails WITH attachments which are not ASCII format. Encrypted e-mails without attachmoments or in ASCII format will be delivered.

oh! i suppose i underestimated the severity of it. apologies!

Form my understanding this needs to be fixed urgently.

So for me, sending encrypted attachments by selecting them from disk works fine for attachments. up to ~200k (I haven't tried larger ones).

Pretty obvious. Thanks.