I'd recommend that you use IMAP. This situation is pretty much what IMAP was invented for.

What is the point of having messages on a server that you can't see in the client?

However, I don't see why the "leave message on server" setting won't work for you. You do have this set on both machines?

Zenos, thanks for the response.

First, I definitely have ""leave message on server" set on both PC and laptop.

Second, I'm reluctant to reset to IMAP for several reasons. Please correct me if I'm misunderstanding something.

(1) It's my understanding that with IMAP you're not downloading the messages onto your own computer, you're looking at them on the server. If this is true, it would not work for me when I'm in places where there's no Internet connection. And besides, I want to keep my own copies of all messages.

(2) I've also been told that IMAP tries to "synchronize" computer with server. So If I delete a file, I'm actually deleting it off the server. I don't always want this to happen.

(3) Basically, I want to have copies of the files on the server and leave the server files alone unless I actually log in to it to manage files there. Don't know if this is possible with IMAP. Also, if I do something on one computer I would not want it to affect what the other computer has access to.

Thanks

..

1) Wrong. Thunderbird makes local copies so you can see previously received messages when offline.

2) Yes. So you're going on a trip. That would suggest a short stay somewhere else. Just don't delete anything you want to keep. OTOH, anything you don't want and do delete will be gone and you won't have to delete it again when you come home.

3) Well you can create folders on the server and not subscribe to them in Thunderbird, so you won't see and cannot delete the messages in them. But frankly, I just don't get it. If you don't want to see certain messages, put them into appropriate folders and don't look at them.

You seem to have talked yourself out of IMAP on the basis of incomplete understanding. Why not try it rather than explaining what you think might be wrong with it?

All of my accounts bar one are IMAP-connected and the sole POP-connected account which I keep for reference feels crippled and limiting.

I can give IMAP a try. How do I change account from POP to IMAP?

Add it again as a new account.

You may need to stop the co-existing POP account from working in order to stop it from grabbing messages for itself. Unfortunately there is no on/off switch. Some users suggest disabling an account by giving it a phony user name or server address in its settings. Just adding ".disabled" to the existing server name would do it. You will, temporally at least, get some error messages when Thunderbird cannot find this server.  :-(

If you find that you can live with IMAP, in your position I would move messages that I wanted to keep from the POP account into either the new one, or to Local Folders, then delete the POP account. If you find that you wish to go back to POP after your trip, again rescue any messages you want to keep then just delete the later IMAP version of the account, and re-enable the POP version by resetting its server name to the correct value.

Ah. I just saw this in the newsgroup. I don't know if it is accurate or correct.

"Gmail POP will let you download mail only ONCE, which makes it a nuisance to use on more than one device. BUT try disabling POP at the website and then enabling it again. All the mail is "new" and you can probably download it with TB."

Now, if that is true, it would explain your experience. It's always rather tiresome when a server has quirks like this that are not well documented and override settings in the client.