I have used Thunderbird for years. This week I bought a new laptop and downloaded Thunderbird on it, but realized that my address books aren't there. So I opened my old computer to try to transfer them but could not figure out how to export the address books to the new computer. I found a link re exporting address books for Thunderbird on lifewire.com, but the instruction steps do not correspond to my "old" Thunderbird interface. Fiddling around with that has not revealed steps that will make it work. This could be serious. Any ideas?