Clamav :Can't read main.cvd header from db.local.clamav.net

Bonjour,

Lorsque je tape:

tail /var/log/clamav/freshclam.log

J'obtiens ceci:

Sat Sep 10 15:34:46 2016 -> WARNING: Can't read main.cvd header from db.local.clamav.net (IP: )
Sat Sep 10 15:34:46 2016 -> Trying again in 5 secs...
Sat Sep 10 15:34:51 2016 -> ClamAV update process started at Sat Sep 10 15:34:51 2016
Sat Sep 10 15:34:51 2016 -> WARNING: Your ClamAV installation is OUTDATED!
Sat Sep 10 15:34:51 2016 -> WARNING: Local version: 0.99 Recommended version: 0.99.2
Sat Sep 10 15:34:51 2016 -> DON'T PANIC! Read http://www.clamav.net/support/faq
Sat Sep 10 15:34:51 2016 -> main.cvd is up to date (version: 57, sigs: 4218790, f-level: 60, builder: amishhammer)
Sat Sep 10 15:34:51 2016 -> daily.cld is up to date (version: 22200, sigs: 603798, f-level: 63, builder: raynman)
Sat Sep 10 15:34:51 2016 -> bytecode.cld is up to date (version: 283, sigs: 53, f-level: 63, builder: neo)
Sat Sep 10 15:34:51 2016 -> --------------------------------------

J'ai alors essayé ceci:

 sudo /etc/init.d/clamav-freshclam stop
sudo freshclam -v
sudo /etc/init.d/clamav-freshclam start

Et là, plus aucun problème:

tail /var/log/clamav/freshclam.log
Sat Sep 10 15:45:41 2016 -> --------------------------------------
Sat Sep 10 15:45:41 2016 -> freshclam daemon 0.99 (OS: linux-gnu, ARCH: i386, CPU: i686)
Sat Sep 10 15:45:41 2016 -> ClamAV update process started at Sat Sep 10 15:45:41 2016
Sat Sep 10 15:45:41 2016 -> WARNING: Your ClamAV installation is OUTDATED!
Sat Sep 10 15:45:41 2016 -> WARNING: Local version: 0.99 Recommended version: 0.99.2
Sat Sep 10 15:45:41 2016 -> DON'T PANIC! Read http://www.clamav.net/support/faq
Sat Sep 10 15:45:41 2016 -> main.cvd is up to date (version: 57, sigs: 4218790, f-level: 60, builder: amishhammer)
Sat Sep 10 15:45:41 2016 -> daily.cld is up to date (version: 22200, sigs: 603798, f-level: 63, builder: raynman)
Sat Sep 10 15:45:41 2016 -> bytecode.cld is up to date (version: 283, sigs: 53, f-level: 63, builder: neo)
Sat Sep 10 15:45:41 2016 -> --------------------------------------

Mais le lendemain, lorsque je redémarre le pc, le problème réapparaît.
Quelqu'un a-t-il une idée?
Merci.

Compliments,