Evgeniy Berdnikov via Exim-users wrote on 19.11.2021 09:16: >>> Yes, "References:" has 1018 octets while RFC limit is 998. >>> This is known bug for several Outlook versions. >>> >>>> Not sure how to mitigate this one. Maybe I should truncate/remove the >>>> header - and possibly break the thread? >>> >>> Better solution is to fold this header (split over multiple lines). >> >> How do I achieve that with exim-4.95? Config option?? > > There are several variants to try: > > 1. Use header add/remove directives in ACLs and/or routers to "reinstall" > problematic "References:" header if its length is too high, in hope > Exim would fold it correctly.
Exim doesn't fold such headers correctly. > 2. Use transport filters (ch.24) on delivery stage. Even if the transport filters correctly fold the headers, the max_received_linelength variable will not be recalculated and may still be greater than message_linelength_limit. And the error "message has lines too long for transport" will still occur. This error will occur even if a very long header is removed. > 3. Route all incoming mails through external filter (such as Amavis), > it should reformat broken mails and re-inject them back. > > I use variations of N3 with custom scripts, those configuraions are > complex and they can't be reduced to a single config option. > > I have no experience with N1 and N2... Just try, it's interesting > are they working variants or not. > > As ultimate solution, you can check for length of "References:" header > and remove it if length is too long. This variant should always work. > -- Best wishes Victor Ustugov mailto:[email protected] JID: [email protected] public GnuPG/PGP key: https://victor.corvax.kiev.ua/corvax.asc -- ## List details at https://lists.exim.org/mailman/listinfo/exim-users ## Exim details at http://www.exim.org/ ## Please use the Wiki with this list - http://wiki.exim.org/
