importexport add on will not open or add itself to 'add-ons'. Appears to be blocked by 'firefox' or otherwise refers to 'connection failure'.
Unable to import contact or emails to 'thunderbird. Have them backed up as .eml and .vcf files in separate folders.
Have followed the instructions in your link https://support.mozilla.org/en-US/kb/switching-thunderbird#w_importing-windows-mail-contacts
relating to "...install the MoreFunctionsForAddressBook add-on following these instructions....."
The .xpi file has been downloaded but will not open or accept being moved to 'add-ons'
Before abandoning 'thunderbird' I would appreciate some assistance.
thanks in advance.