Maybe there are still bits of ZoneAlarm left on your system. Which could be conflicting with the
Sygate install.
Just a thought.
Ive not done this manual uninstall. But it is how I was instructed to do so.
I (and many others) have been experiencing problems with ZoneAlarm, since the last upgrade in Sept or Oct. Although there is a new update available just recently, I havent gotten up the nerve to install it yet.
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Running Zone Labs security software simultaneously with other firewall software may cause conflicts - We recommend that you not run other PC firewall products (such as PC-Cillin, Kerio, Sygate) simultaneously with Zone Labs security software.
QUOTE
Uninstalling ZoneAlarm
To make sure that you can see the ZoneAlarm system files, if they are still on your computer:
a. Right-click on Start, then left-click on Explore. When the Windows Explorer panel appears:
- In Windows 95, 98, 98SE: Click View -> Options (in Windows 98/98SE, this will be called "Folder Options"). Click the "View" tab, then click the "Show all files" radio button.
- In Windows ME, XP, 2000: Click Tools -> Folder Options. Click the "View" tab, then click the "Show hidden files and folders" radio button.
b. Make sure you also UNcheck the box to "Hide Protected Operating System Files" if you have one.
c. When searching, be sure it searches ALL hidden files and folders (in XP: check Advanced search settings)
d. Click OK.
IMPORTANT NOTE: Making modifications to system files may disable crucial functions of your Windows operating system. We strongly suggest re-enabling the "Hide files and folders" feature once all ZoneAlarm files have been removed.
Click on Start, then Search or Find, and select Files. Make sure that the location box is set to search your local hard drive (usually C or All Local Drives.
Type the following exactly and delete the folder:
zonelabs (under your SYSTEM or SYSTEM32 folder)
"zone labs" (under your Program Files folder)
"Internet logs" (under your Windows or WINNT folder)
Type the following exactly - delete files found in \Windows or any subfolder below it, in your \Temp folder, or in the Windows "Pre-Fetch" folder):
vsconfig.xml
vsdata.dll
vsdata95.vxd
vsdatant.sys
vsmon.*
vsmonapi.dll
vsnetutils.dll
vspubapi.dll
zaplus.*
zapro.*
zllictbl.dat
zlparser.dll
zonealarm.exe
zoneband.dll
vsutil.dll (please right-click, Properties -> Version to be sure it is a ZA file. Do NOT delete this file unless it is a Zone Labs file!)
Make sure your Recycle Bin is empty (right-click and select Empty).
REBOOT
NOTE: If you received an error message upon deleting the files, or if the original programs remain in the Programs list, or if the problem persists after this, removing the files in Safe Mode will allow you to delete the files properly. Click Start, Help, and search for "SAFE MODE" for information specific to your system.
I also made a cd for any future needs. 
