Is there a way to force postfix to add a "Content-Transfer-Encoding" line to the header of DSN ("Delivery Status Notification") messages? May be some clients / Groupware systems (like zarafa) have problems if the "Content-Transfer-Encoding" was not set correctly (see also https://forums.zarafa.com/showthread.php?91-Fallback-delivery ). If I look in the header of the DNS message I cannot find a "Content-Transfer-Encoding" entry.
1 Answer
It's in my case a bug in the currently newest zarafa version (ZCP 7.1.8-43801):
https://jira.zarafa.com/browse/ZCP-12019
According to zarafa the error is corrected in the next few days.