ZoneAlarm Causes Chkdsk not to function

Just discovered a problem with the latest Free and Pro editions of Zonealarm
version 50.590.043

I was trying to get chkdsk to scan my harddrive for errors and it displayed
the message "cannot open volume for direct access" even when running at boot
time before windows XP has loaded. I figured it was because something had a
lock on the files so pressed F8 to load safe mode command prompt which also
hung.

Did a quick google and it's a known problem with ZoneAlarm. See
ZoneLabs site

Disable or uninstall Zonealarm and it works fine. Rumours about XP SP2
fixing it, although MS will probably recommend using the newly enhanced and
built in ICF instead of ZoneAlarm and that will "fix" it.