I am seeing incoming emails rejected by Discourse with:
Email can not be processed: Access Denied
Incoming email itself appears to be working correctly. The message reaches the mail receiver, and SPF, DKIM and DMARC all pass. Discourse then processes it through Jobs::ProcessEmail.
The behaviour appears dependent on the MIME/body content:
- simple/plain email → accepted
- email containing an Outlook signature, table and/or inline images → rejected with
Access Denied
The rejected email log shows the failure occurring in Email::Processor#process!.
Discourse application version:
4143157a17dc3ff63c909c64d0cf578243d38861
This installation was recently migrated/restored to another server, but incoming SMTP delivery itself is functioning and the behaviour seems specifically related to richer email bodies.
I can provide a sanitised raw MIME message and further IncomingEmail/Email::Receiver diagnostics if useful.