Well I'm going to stick my foot in my mouth and blame ZA privacy settings

Problems logging in were a problem with web shield, ZA Pro and Privacy settings set to High. This was commonly logging into say hotmail, yahoo, etc. were you start on an http page enter your log on details it is validated and directed to an https page and sometimes back. Somewhere in this flip flop (http {web shield} https {no web shield} http {back through web shield}) the privacy function blocked the transfer of the logon details, why I haven't a clue, but that was more or less what happened.
avast tried to overcome this by using the disabling of the Transparent proxy and this seems to work fine.
Now somehow I think this is happening again with galloway_777, why is the issue, transparent proxy still working or something else, is difficult to tell. You could also try lowering the ZA Privacy function or temp disabling it and see if that works and allows logon. If not you need to check the web shield transparent proxy has been disabled and your browser proxy connection settings have been correctly entered. I know you have been through this before, but short of that I would suggest you uninstall avast, boot, install and ensure you start off answering YES when the compatibility question arises.
Use a text editor and edit the avast4.ini file, the default installation location is C:\Program Files\Alwil Software\Avast4\DATA\avast4.ini (I would advise you copy avast4.ini before editing it, just in case).
If you answered incorrectly, Locate the line containing ZoneAlarmCompatibility= and delete that line (avast will ask again, answer YES) or change the value to =1. Save the edited avast4.ini file.
If you are using ZoneAlarm Pro and Privacy Control in ZoneAlarm is set to High and if you click YES in avast compatibility dialogue box the transparent mode proxy in web shield will be turned off you have to manually configure browser to access internet. To manually configure your browser watch instructional video
For IE - broadband users: -
Tutorial - Web Shield Proxy Set-up for IEFor IE - dialup users -
Tutorial - Web Shield Proxy Set-up for IE (Dial-up)For Firefox users -
Tutorial - Web Shield Proxy Set-up for Firefox