clamav uses /var/run/clamav/clamd.sock for its socket location. amavis uses /var/run/clamav/clamd for its socket location. By default, these do not match and headaches ensure from this subtle difference. ClamAV's clamd.sock sounds more logical and may be used by other applications, thus amavisd should be default also specify clamd.sock. Reproducible: Always
Those are the default sockets from their respective packages. Change one or the other to match in new installs. Changing either socket and breaking existing installations is not a good choice. Closing as invalid.
I tend to disagree. ClamAV sets up its socket. Amavisd connects to THAT socket. I don't know when or where amavisd decided to use that socket, but clamav appearantly changed its naming a good wile ago. I'm NOT talking about amavisd own socket, but about clamav's socket only. I can agree that changing either socket and breaking existing installs is bad, but shouldn't be avoided to improve and correct future installs. Taking it upstream to amavis.
Thankfully, amavis dev's agree ;) "Agreed, thanks for the suggestion. Will be changed for 2.7.1 and 2.8.0: - ClamAV-clamd and ClamAV-clamd-stream av scanners: changed socket name in a sample configuration file amavisd.conf to /var/run/clamav/clamd.sock (previously the socket name was /var/run/clamav/clamd); this makes it compatible with a default socket name under at least Gentoo and FreeBSD; Mark" So expect this change in the future.
Just a brief update, this change has since been merged and released so shouldn't be a problem anymore.