I presently have a working POP3 account on my Windows 7 laptop. I want to transfer this account to my Window 11 PC.
It contains many folders and emails.
On my Windows 11 I have downloaded Thunderbird, but all my emails are just in a few folders.
I need to know please, of a system/process whereby I can back up this POP3 data, and transfer it in situ, into my Thunderbird account which is IMAP?