Ever since Avast free edition updated to the latest level it appears to block email communication within Chaos Intellect, with the following error 'Login failure An established connection was aborted by the software in your host machine.'. Disabled Avast shields, email goes through without a problem. Added Chaos Intellect to exception list ... made no difference.
Test within Chaos Intellect of incoming/outgoing connections to server - test fine. Pop3 email accounts.
Assume problem is Avast as it started after the update, but with contact Chaos Intellect support as well.