I have just installed ZoneAlarm Free 6.5, switching from Windows Firewall. My System details are Compaq Presario P4, 256 MB RAM, XP-SP2, AVG Free 7, Ewido Anti-spyware 4.0, DiamondCS ProcessGuard Free 3.405.

I had done TrendMicro onlinescan earlier without a hitch. But after installing ZoneAlarm, I am unable to do so. I even shutdown ZoneAlarm and switched on Windows Firewall, but now even Windows Firewall blocked TrendMicro traffic.

Shall be grateful for advice please. Thanks,

You are probably correct. They are probably blocking the ActiveX control that those on-line scans use. ActiveX blocking is important to do, and it helps prevent malware from being silently installed. The ZA logs should tell you what it has blocked. I suggest that you use scans other than from the on-line ones. If you suspect malware is on your system, I suggest that you go through CC's Malware Removal and Prevention Procedure. That can be found here:

http://wiki.castlecops.com/Malware_Removal_and_Prevention:_Introduction

Thank you for your view. Would any other online scan (kaspersky / a-squared / bitdefender) work seamlessly with Zone Alarm?

Secondly, I did not understand why, even after shutting down ZA, my old Windows firewall suddenly jumped into action.

As regards ActiveX, I also have SunJava enabled and I had tried the alternative Java-based scan of TrendMicro, but it too did not run.

Also, ZA shows one blocked entry : Rating medium, Protocol UDP, Program svchost.exe, Source 192.168.1.2, Destination 218.248.255.145 (my ISP), Direction outgoing. Since I am new to non-Windows firewall, kindly let me know if this might represent the traffic going from my PC to Trendmicro Housecall through my ISP?

Finally, maybe a bit off-topic, what if I go for AVG's paid AV-cum-firewall, since I am so comfortable with AVG (so far)?