The security certificate presented belongs to"(.carrierzone.com,carrierzone.com)"
      How do I cancel this connection and get back to a straight  "mail. fairpoint.net" connection? Thanks

I am running thunderbird on an older mac osx on an imac g5. I recently upgraded my OSX to the newest my g5 could handle, and found that the newer versions of thunderbird would not install on my osx. Since thunderbird had somehow been deleted from my applications in the process, I went online to find an older Thunderbird app that was compatible with my system. Since doing this I get the security error "domain name mismatch" popup when opening emails. Since I often transfer alot of personal finance and tax info via email, it is a concern to me that my emails are passed on through a third party. How do I remedy this problem and eliminate the popupwarning? The security certificate presented belongs to"(.carrierzone.com,carrierzone.com)" How do I cancel this connection and get back to a straight "mail. fairpoint.net" connection? Thanks