After many frustrating hours trying to configure my PC and 2 laptops and a friends business PC and laptops into networks I just gave up. I had tried everything I knew including deleting ZA and AVG and while the PC could see the other computers they could not communicate. There were times when I had changed a setting in the registry file that things would work but with in a short space of time they stopped again. Finally I talked at length to MS technician for 2 hours and finally narrowed it down to 2 things. ZA is changing the settings in the registry that disables the communications between the IPv6 and the Tereodo Tunneling adaptor. The only thing in the end I did wrong when I had tried uninstalling ZA was when I went to edit the registry file was not to start the regedit as "Run as administrator". Like many others I felt being the only one using the computer as administrator it worked like XP. Not so apparantly. You need to type in the "Search programs and files" area when you click on the start button, then right click on the rededit.exe and select "Run as administrator" Then any changes you make will be saved.
For details on the solution you can read a post here http://tiny.cc/VShTf
Until ZA addresses this issue I will not be re installing ZA. Admittedly it has been a copy of the free ZA version but is still a problem.
Operating system are Win 7 pro 64 and 32 bit.