You might try creating a CSV file for the process, as it uses common names for all phone numbers, e.g., home phone, work phone, mobile phone.

Thank you for the prompt reply. I had a CSV file on a stick that I lifted from the 2012 Outlook program on the old WIN7 machine. I imported it into the Thunderbird 102 software on the WIN 11 machine and I got over 1,000 addresses but almost all of them only display the first name (I unchecked everything on the matching screen in TB before I executed the download. Only used first name, last name, work phone and cell phone for the match. I believe I got the headers matched out but now the list, excepting a couple of contacts that I had typed in earlier came up only displaying the first name with the emojo (sp) of a head in a circle with a lot of garbage characters (commas, quotation marks, etc) Is there, perhaps, something wrong with the file I downloaded from the old machine? Thank you

Are you familiar with Excel or a compatible spreadsheet program? If so, I suggest opening there and simplifying the layout by deleting unneeded columns. This also lets you see column titles, which should be the top row. That can help you, as you then see the actual content. And the column titles. My suggestion is to highlight all unneeded columns and delete.

If you have any confusion, I suggest creating a single entry in addressbook, and then highlighting the addressbook, rightclick and export as csv. Open that file also in Excel or compatible and you will exactly what the Thunderbird naming structure is and column layout. That can educate you to whatever naming you need.