I see empty emails in Outlook as a result of an add-in conflict.
I have seen similar issues with other add-ins, such as T3934; I'm submitting this hoping that more information/scenarios can help find a workaround/solution.
I have the following add-ins in Outlook 2019 (Microsoft 365 Apps for Enterprise, using Exchange Online).
I deactivated the plugins individually (by removing the ticks in front of them) and concluded that the combination of ESET and GpgOl causes the problem.
When I deactivate the ESET add-in, GpgOl works fine. The email opens and decrypts as expected. This is the log for opening an email in the preview pane in this scenario (please let me know if I cut off too much):
When I deactivate GpgOl and reactivate ESET, I see the attachments incl. the asc file.
When both add-ins (ESET & GpgOl) are active, the email shows completely empty: I see the sender & subject, but neither content nor attachments. This is the bit I don't understand: GpgOl must be doing *something*, otherwise the attachments would still show, right? Log for this:
gpg4win version 4.0.0
Windows 10 Pro (20H2/Build 19042.1466)