Oh dear
I removed e-trust OK. Nothing nasty left in the registry, but the Start-up check stayed in the Startup programs and kept telling me to update my registration. That was disabled with Winpatrol. I'll delete it later.
Avast installation started OK but at the end announced it was incompatible with ZoneAlarm and that my browser (Firefox) needed to use a manual proxy. I followed instructions to set it up, but no joy - no net access.
Avast say they are working with ZoneAlarm to fix this but it all seemed too messy. Also I wasn't sure if I should use the proxy with Thunderbird or IE which I use occasionally, and what about FTP, SSL etc settings in Firefox?
So for the time being I'm back with AVG which I was using before the new PC and e-trust
I may check NOD32 which gets good reports. Anyone know problems like Avast's with that?