Two security companies whose firewall offerings were incompatible with Microsoft Corp.’s Windows 2000 Service Pack 1 have fixed the problems with updates.

Last-minute changes to the service pack – released July 31, five-and-a-half months after Windows 2000 was launched – caused firewalls from Network ICE and Zone Alarm to crash. Both companies have updated their products to fix the bug.

A patch for ZoneAlarm 2.1, available for download at, was released a couple of days after Windows 2000 Service Pack 1 came out, according to the San Francisco-based company.

Over the weekend, Network ICE, based in San Mateo, Calif., posted a patch for BlackICE Defender 2.1 at