Cannot log in because certificate re-definition window opens. Says "You are about to override how Thunderbird defines this site. Legitimate banks, stores and other public sites will not ask you to do this. " The window lists the site, then states "Wrong Site: This certificate belongs to a different site, which could mean that someone is trying to impersonate this site." Two boxes are available for response: "Confirm this security exception" and "Cancel." I do not want to "confirm this security exception" because I do not want to fall victim to some malicious attempt. If I click on "Cancel," I cannot receive new e-mail. Suggestions?