Once again Bassfisher is on the money about the ZoneAlarm AV and Firewall software. They have had issues going back to Windows98SE. Most major corporations do not use this product. Yes, it's free and yes, a lot of people use it--but a lot of people pay too much for their Auto Insurance (what is this a Geico commercial!?). Doesn't mean it's gonna be good.
As far as your comments about the Windows Defender AV & Firewall that comes with Windows8; that's still open for debate. Many moderators here and on other Tech Forums I participate in say yes, it's great; and others like me who repair broken Windows8 computers say "no". I've never been comfortable relying on Microsoft for my protection, and that goes back to 1980 when Anti-Virus protection just came out. The report you mention is just one of many that gives the Win8 defender low marks. Microsoft is good at many, many, things, but one thing the have always lagged in is A-V protection and security software.
It is NOT their primary business, nor is it likely to be anytime soon. It's kind of like buying a high-performance fuel-injection system for your car from a muffler shop--they really don't know fuel-injection systems, as it's not their primary business, but rather a sideline-business, much as A-V software is for Microsoft. Enough on the Analogy here I think you get it by now.
The most common mistake my Customer make is that if 1 A-V program is free, why not 2? Or 3? Or 8? Yes, I've had Customers with 8 A-V programs all running at the same time. That's never worked well, and it hasn't worked at all since 2003. You need to check your Control-Panel-->Uninstall Programs and eliminate all other A-V programs, such as Norton, McAfee, Trend Micro, AVG, Avira, etc. and just pick one. I'm liking Avast a lot; and I've had great success with it in the last year (over 200 Million Users worldwide). Their product blocks many of the new Ransomware viruses such as the FBI virus that Norton and the other big guys have NOT caught. I still use Norton on my main computer, but I have replaced it with Avast on about 25 Customer computers, and I have only had 1 computer come back with Avast running with a Virus, and that's cause the Customer let the Grandkids uninstall the program from their Windows Admin User account.
My suggestion is to remove all instances of the ZoneAlarm AV+Firewall AS WELL AS WINDOWS DEFENDER.
If you can't remove the Defender (that can be tricky), simply disable it. Pick Avast or one of the other well known A-V programs or better yet go with an Internet Security Suite. This will set you back from $40-$70 per year per computer but is the best possible protection. Remember that none of these products are 100% perfect! If anyone tells you that, don't believe them.
BTW, the Avast AV 2014 Free Edition is the last truly "FREE" antivirus, and I believe the best.
The rest of the guys who used to be free like F-Prot and AVG all had to succumb to competition and only are free for about 30 days and then they turn themselves and their protection off on your computer--until you feed them a Credit Card number!