We are still getting messages from readers cut off from the internet following a massive Microsoft update last week designed to thwart a newly-discovered hole in Domain Name System protocolsthat govern internet addressing. The hole, which was not restricted to Microsoft software, could allow attackers to redirect traffic from legitimate sites to criminal imitations.

The KB951748 update cut off thousands users of ZoneAlarm firewall software, including the free basic version.  This was because it changed the range of ports used for DNS calls to include ones blocked by ZoneAlarm, and publisher Checkpoint was apparently not informed of the change.

Checkpoint has posted fixes here.