Hey there,
I know this is a bit late, but in case you’re still looking for a solution—or if someone else stumbles upon this thread—here’s what you need to know:
I’m also a Dashserv customer, and this issue is due to a limitation with their DNS. To fix it and get everything running smoothly, check out this post: Dashserv DDoS Protection.
If that link is no longer accessible, you can manually adjust your configuration with the following steps:
cd /opt/mailcow-dockerized
echo "forward-zone:
name: \".\"
forward-addr: 1.1.1.1
forward-addr: 1.0.0.1" >> data/conf/unbound/unbound.conf
docker compose restart unbound-mailcow
This should resolve the issue