Maybe noone noticed my last comment in Provider Overview and therefore I opened this seperate topic. Hopefully someone has experience about.
A colleague of mine installed v0.100.0, created a new free account at outlook.com.
Mails sent from v0.100.0 to me without encryption are displayed at my phone (v0.20.0 and Thunderbird with Enigmail).
After I did first reply next mails from v0.100.0 peer are shown as empty mail with two binary attachments (ATT00001, 12 Bytes; ATT00002.bin, 2021 bytes).
Both parts are encoded as “Content-Transfer-Encoding: base64”
No pgp part is seen in message source! No plain text part is seen in message source!
==> no idea about root cause for that behaviour. But message is full of MS specific headers and autocrypt header is not to be seen in headers!
Then switching with same installation to a gmx accout ==> all works fine as expected !!
Does anyone have an idea?
In any case whether outlook.com needs special preparation or setting changes or ms changed behaviour of mail server.
But what is clear now is that description here about outlook.com/hotmail.com seems to be wrong meanwhile!