A lot of important and useful information is posted to litsupport each week. The following is a distilled summary, in the form of questions and answers.
Q. How would one export e-mails from Thunderbird to import into Outlook?
1. Thunderbird is an open-source free email client hailing from Netscape and currently part of Mozilla. It may use the IMAP or POP3. The choice of the export method depends on the metadata requirements. Keep in mind that few MIME email package store attachment dates, so those may be lost.
2. Aid4Mail is a commercially available software supporting multiple mail formats;
3. Use IMAPSize to convert to .eml, then convert to PST or import into LAW, see detailed instructions here;
4. It's important to note that Thunderbird uses two files and the one containing the messages doesn't have an extension, see more details here;
5. Check out the tutorial here;
7. As with all conversion of documents, one should perform thorough tests as to the accuracy of the results compared to the original data, and also take note of what meta data may have been lost (or gained) during the process.
This summary from the Litsupport Group postings created by the wonderful and talented members of the group has been culled by Mark Kerzner (firstname.lastname@example.org) and edited by Aline Bernstein (email@example.com).