You have to install their security certificate so the can undertake a man in the middle hack of all of your communications. What Avast do not say is they can not scan any of your SSL communications (Secure) because it is encrypted. Looking further I managed to find a note on managing the redirect settings where the advise that the ports used areīy default, standard port numbers are specified for each protocol as listed below: Then we have the next worrying statement 'For Mail, the default ports are the standard port numbers for the four basic email protocols.' I get the feeling that again they are only scanning non encrypted mail traffic. It is reserved for non encrypted connections. Any web page starting with HTTPS (and that is most of them these days) do not use Port 80. 'For the Web, Avast normally monitors only communication through port 80.' IF you are reading this on the Mozilla support web site you are not communicating on port 80. I can see some glaring holes in what they claim to do and what they actually do.

I would really like to get this issue fixed. I think I can work around the issue, but doing a fresh install of the OS, but that will not address the bug that is causing me to be unable to connect to gmail. I get a yellow triangle with an exclamation mark in it, saying Configuration could not be verified - is the username of password wrong? When I try to configure an account, I use the defaults for pop, which are SSL, 995, and SSL/TLS. I also deleted all files and directories in my user profile that had the word thunderbird. I uninstalled thunderbird, and deleted my profile directory. Going back to my mail computer, I uninstalled thunderbird, and then reinstalled it. Using a separate computer that has never had thunderbird installed on it, I was able to successfully configure thunderbird to get gmail via pop. I can pop to other mail servers without issue. I also have a test gmail account that has the same issue. I have set gmail to single authentication, and enabled it to pop email.

Last weekend, I was unable to retrieve email. I have been using thunderbird and gmail (pop) for several months without issue.

Thunderbird not working with gmail