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Welcome to the forums, jfd!
So, your connection problem should be solved with David's suggestion ... right?
Concider using Zone Alarm Free as your firewall. I have used this for over 5 years with much success and many others say it is one of the easiest to use for beginners. You can also use the Search button at the top of the page to search for other firewalls as this has been addressed on this forum many times.
Whatever firewall you decide to use, be sure to remember to allow all avast services (ashMailSv.exe, ashWebSv.exe, etc) access to the internet.
Please come back often, learn more, and maybe help others.
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