Trodde i utgangspunktet egentlig ikke på av ZoneAlarm virkelig skulle fucke op Apache, men se her:
http://www.apache.jp/dist/httpd/binaries/win32/ZoneAlarm Users Read This First
If you will install Apache 2.0 on a PC with ZoneAlarm installed, you may discover that Apache 2.0 stops responding, and that when you stop the Apache 2.0 server or shutdown your machine, you may experience crashes (BSoD, or the Blue Screen of Death).
No further details are available at this time. See the following bug report for the details and observations that have been collected;
http://nagoya.apache.org/bugzilla/show_bug.cgi?id=7932 The Apache HTTP Project does not support using ZoneAlarm, or other software firewall solutions in conjunction with Apache. It is the user's responsibility to determine the compatibility between any firewall product and the Apache HTTP Server.