I too cannot update the virus and spyware software/signatures. I am using ZoneAlarm Security Suite version: 10.0.250.000 and have just renewed the license.
The anti-virus engine version is: 18.104.22.168.
It is running on Windows7 (64-bit).
Do you need further information to address this? The problem has been going on for a number of days and seems to have coincided with the license renewal.