The problem was solved, by manualy installing (using a2enmod) the next modules, that installation script doesn't install (neither from clean install, nor from apt- get dist-upgrade). So, after doing a2enmod for each of the next modules and
auth_anon auth_basic auth_dbm auth_digest authn_alias authn_anon authn_dbd authn_dbm authn_default authn_file authz_dbm authz_default authz_groupfile authz_host authz_owner authz_user include userdir vhost_alias And after that /etc/init.d/apache2 force-reload the problem was fixed, apache2 started and nagios worked fine. -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]