Help/Troubleshooting Information, click Open Directory to open the profile folder in File Browser, close TB. Open the Mail/Local Folders subfolder, and copy the mbox files to that location. When you restart TB, you should see subfolders of Local Folders with the same names as the mbox files.

In Thunderbird, Troubleshooting Information>Open Directory shows the folder ~/.thunderbird/jq5wpu1a.default. I closed Tbird, opened this folder; it contains about 60 items, looks like mostly scripts and databases. In this folder, created a symlink named "Local Folders", linking to the directory containing my mail archive.

Reopening Thunderbird, I see an item "Local Folders" on the left side of the screen. There are two items listed, "Deleted" and "Outbox". My local archive is not listed.

You shouldn't create a Local Folders folder in the profile folder; it already exist as a subfolder of the Mail folder. Just copy the mbox files into ..Mail\Local Folders while TB is closed. If you want to change the location of Local Folders, see this article:

http://kb.mozillazine.org/Local_Folders

Copied one of my mbox files into the folder : ~/.thunderbird/<local name>.default/Mail/Local Folders The next time I opened Thunderbird, the mbox file was visible under "Local Folders" and selecting it gave a list of the messages stored in the file.

Thank you for your assistance.

Next step is to see how Thunderbird handles saved attachments (pictures, documents, etc.) stored with the archived mail.

Attachments are encoded along with the message body, either in mbox format or eml, so if they are still attached, they should be visible when you open the message.