ATTENTION: If you have this problem, read the solution at the bottom of post.

I have discovered a flaw that has been in the Zone Alarm Security Suite for over two years. Up until three weeks ago, I was using an older computer. (p4 2.6 ghz, 1 gb of mem, etc.). There have been several occasions within the past two years where I have downloaded and opened .exe files or auto zip files bigger than 1gb. On these occasions I would notice that Windows Explorer would hang for several minutes. When control got returned, the computer would from that point forward become permanently slow. Programs would take minutes to open, shutdowns would take over 10minutes, opening files was a problem. The first time, I thought maybe I had a virus of some sort so I did a scan which turned up nothing. I tried multiple scanners but still found no Trojans, viruses, or malware. After trying several other fixes, I gave up and reformatted. The computer returned to a healthy state and I concluded that the problem must have been a windows related error. After another few months I had the same exact problem caused by the same exact method.

At this point, I checked my hard drives. One of them was failing. I was able to save my data onto a new hardrive but figured another reformat couldn t hurt. Now, running off a brand new hard drive I figured that would be the end of my troubles. Much to my dismay, the problem returned a few months later, again after opening a large exe. Now I was getting desperate. I did a full system diagnostic but that found nothing wrong. Not knowing what to do, I reformatted for the unth time knowing that it would at least get me a few months of peace. Shortly after, my motherboard died and so I replaced it. The problem persisted.

The cycle continued, and each time I reformatted it went away. Two weeks ago, the problem returned. After pulling hairs for hours trying to finally figure out once and for all what was wrong I realized it had been Zone Alarm. Task manager showed Vsmon.exe as making over 2,000,000,000 I/O Read Bytes per minute at startup. Opening programs added another billion. Closing them did too. Basically any action caused a spike in I/O reads. I couldn t even get into Program Manager to uninstall Zone Alarm so I tried the next best thing, and downloaded an update from the site. I chose upgrade and let it do its thing. Upon rebooting it was obvious that this had no effect

I then went into Safe Mode to uninstall from there. After several attempts I was able to get it off. When I rebooted everything was back to normal. My computer ran like it was brand new. I still loved Zone Alarm so I reinstalled it. Still, everything was fine.

Fast forward to now. I built a new computer and scraped my old hard drive. I didn t reformat but this wasn t a problem, everything worked smoothly.

Two hours ago I wanted to install a new program. The file was over 1gb. I figured that it should be no problem for my new machine, regardless of Zone Alarm. This was a big mistake. The computer has clearly degenerated now. Its not as bad as my old one when it had this problem but it is still noticeably slower. Here is a picture from Task Manager and Process Explorer to show the problem.

I m going to wait before I reinstall Zone Alarm in case any further analysis is required.

Just to recap:
1. The problem stems from opening a file greater than 1gb on Windows XP.
2. Windows Explorer will hang for some time and then the exe will appear.
3. Zone Alarm will now permanently have high I/O read bytes.
4. Upgrading Zone Alarm will not fix the problem.
5. Only a full uninstall and clean install will fix it.

My current Specs:
Windows XP Pro Service Pack 3
Asus P5E
Intel E8400
2gb Corsair Dominator ram
Nvidia 8800GTS 512
Creative Sound Blaster Audigy 2ZS

My old specs:
Windows XP Pro Service Pack 2
Asus P4-soemthing
P4 2.6ghz
1gb ram
ATI X800Pro
Creative Sound Blaster Audigy 2ZS

Operating System: Windows XP Pro
Software Version: 7.0
Product Name: ZoneAlarm Internet Security Suite

EDIT: Let me add that every time this problem occurs there are no performance hits other than a high I/O Read Byte. The CPU remains at low usage. The memory is never used up. Nothing apparent is wrong. That is why it took so long for me to figure out the cause. I/O Byte Read is not automatically enabled in task manager and requires you to edit the view settings in the column manager.

The following workaround is available for this problem.
Set Program Control > Main > SmartDefense Advisor to Manual. This offers the same protection as Auto, just with a few more popup windows initially.

Credit: HammerNU

EDIT (Sep 19, 2008): This problem still persists as of Version It is related to the Smart Defense Advisor. The workaround for this bug is still functional. Lower your Smart Defense Advisor to "Manual" or "Off".

Message Edited by Powerhouse on 06-03-2008 05:39 PM

Message Edited by Powerhouse on 06-03-2008 05:41 PM

Message Edited by Powerhouse on 06-03-2008 05:42 PM

Message Edited by Powerhouse on 06-03-2008 09:56 PM

Message Edited by Powerhouse on 09-19-2008 05:10 PM