Hi @esackbauer
I have performed several tests.
- If I send a new email from ThunderBird to Outlook, I DO see the attachments.
- If I forward a mail with attachments from Thunderbird to Outlook, the attachments are not seen.
- If I forward a mail and add attachments they do not appear in Outlook either.
In any mail client other than Outlook 2021 I do see the attachments.
I have tried to send xls, zip, pdf…. In plain or html format