Hi Nable, hi Heinz. On Di 24 Nov 2015 14:01:36 CET, Nable wrote: > Package: lists.x2go.org > Severity: wishlist > > Dear maintainers, > All messages that were sent from IPv6 address of > freya.das-netzwerkteam.de are classified by Gmail (and possibly by > other mail providers) as unwanted and unconditionally fall into "Spam" > folder. Judging from message headers Gmail is also unsure about > messages from its IPv4 address but acts more permissive. I always use > "Not Spam" button for such false-positives but gmail still insists > that something is wrong with such messages. > > I've noticed this problem about a year ago and now it became annoying > enough to finally file a bug. I don't know the exact reason but it > looks like the problem may hide in the absence of SPF record [1] for > lists.x2go.org as this is the only suspicious thing in mail headers. > Either way, usage of SPF is considered to be a good practice nowadays > and a lot of companies deploy it. > > 1. https://en.wikipedia.org/wiki/Sender_Policy_Framework I finally found some time to look into the above (because one of my customers also made me aware of this). For all my mail domains (unfortunately not x2go.org), I now have set up a SPF TXT record on the DNS hosts. For the lists.x2go.org subdomain a bind9 entry should look like this: """ $ORIGIN lists.x2go.org. @ IN A 178.63.100.243 @ IN AAAA 2a01:4f8:121:5085:250:56ff:fe15:236d @ MX 10 ymir.das-netzwerkteam.de. ; Mail Exchanger for mailing list ; SPF Record for our MXes @ IN TXT "v=spf1 mx a:freya.das-netzwerkteam.de -all" """ @Heinz: Can you deploy this for lists.x2go.org? Thanks. Thanks! Mike -- DAS-NETZWERKTEAM mike gabriel, herweg 7, 24357 fleckeby fon: +49 (1520) 1976 148 GnuPG Key ID 0x25771B31 mail: mike.gabriel@das-netzwerkteam.de, http://das-netzwerkteam.de freeBusy: https://mail.das-netzwerkteam.de/mailxchange/kronolith/fb.php?u=m.gabriel%40das-netzwerkteam.de