Why does old Sympatico sent email not show up in my Thunderbird Sent folder?

[User1231]

My Thunderbird client is correctly showing inbox emails, but it only shows new sent emails, not old (last few years) sent emails.

Can someone recommend the right settings so I can see my old sent Sympatico emails in my Windows 10 PC Thunderbird Client?

[User1231 · Accepted solution]

Problem solved.  Changed to using IMAP instead of POP incoming mail server.