Hi - Running these versions;
ZoneAlarm Free Antivirus + Firewall version: 10.2.047.000
vsmon version: 10.2.047.000
Driver version: 10.2.047.000
Antivirus engine version: 8.2.11.97
Antivirus signature DAT file version: 1085371424
Web Identity Protections version: 1.5.388.0
and
AVG Free version 2012.0.2176

On scanning (I'd had Heuristics on), ZA decided I had malware on my system - OK, so I told it to handle it; It then (without my having any say in the matter) deleted mirc.exe as "possible malware" (fixed that), and also decided that avgcorex.dll (part of AVG) was malware (HEUR.Virus.Win32.Generic) and removed it - thus disabling my (previously working) Anti-Virus.

So, a suggestion, turn Heuristics OFF if you are running ZoneAlarm as just the firewall, and AVG for your Anti-Virus, lest you have to fix it LOL

(I wish I could reach the ZA developers and suggest that they not delete AVG's internal DLLs without seeing if AVG is your active antivirus, but, sigh.) I'll go suggest to GRISoft that they plan to recover easier when this happens LOL