POP3 client not downloading all emails from server

Question

I've an old email account (pop3) with lots of emails that I want to download. I don't care what client - but I'm currently trying with Thunderbird. It says that there are no new emails on the server. However, if I telnet to port 110 and do a "list" command, there's thousands of emails on the server. Why isn't Thunderbird (or any other client I try) downloading these? And is there any way I can get it to do so?

Solution 1

Thunderbird has already downloaded the messages once, and saved their UIDs so that it doesn't download them a second time. To download them a second time with Thunderbird, you need to delete Thunderbird's saved UID database for that POP account.

There are, of course, tools that will download from POP accounts aside from Thunderbird. Since they won't know about Thunderbird's UID database, they, too, will download the messages afresh. getmail, for example, can download a POP mailbox into a local maildir.

Solution 2

They are most likely marked as "Read" already on the email server. Go to the email server and attempt to mark all of the emails as Unread. This will then allow the client to download them.

The client doesn't want to download emails you have already seen/read.

Comments

[Dan]

I'm not sure how to mark them as unread. Can this be done when I telnet into it through port 110?

[David]

What is the OS of the mail server?

[Dan]

Ubuntu. I have root access to it. The mail server is vmail.

[David]

I'm researching this right now. It looks like you could just mass mark the emails with a "+". The "+" means unread. I'm not sure how to do this, but I am reseaching. Let me know if you know how to do this, or understand what to do. If so, please post it for other people so we can be Google friendly.

[Dan]

Thunderbird hasn't already downloaded them. It's a new install of Thunderbird. These emails have never been downloaded - I don't know why they've been marked as read to be honest.

[JdeBP]

Thunderbird must have already downloaded them. This is the only circumstance in which it skips over messages in this way. Messages being marked as read has nothing to do with it. As you saw yourself, that doesn't affect the operation of the POP3 protocol in the slightest. Thunderbird isn't telepathic. It knows only what it is told via the protocol, which has no notion of a "read" message. And it uses UIDs to exhibit exactly this behaviour of not downloading messages twice.

[Dan]

If the protocol doesn't have a concept of "read/unread", then the problem must be something else. Thunderbird has not downloaded them. As I say, I've only just installed it. I've also tried PopPeeper (pop3 system tray notification util), and that doesn't see the messages either. However, I can see thousands of emails if I telnet into onto the server.