Incomplete Download of Messages from POP Servers

Question

I finally convinced my PC husband to switch over to Mac, and I've been gloating for years about how I'd have him up and running in minutes. Well...I've been working on this problem for days now.
He has two POP e-mail accounts, one for work and one Gmail. I originally set him up in Entourage, but encountered this problem: While all his e-mail from his work account downloaded to his Entourage account, Entourage acts as if Gmail doesn't exist. (The account is set up properly, just like on my own machine, and tests correctly, but when I check mail for the account, I'm told there are 0 messages there.)
Frustrated with Entourage, I then went to set him up in Mail. The Gmail account set up with no problem and downloaded all his messages from there. However, now it's the work POP account that won't function: He has 4000+ messages on his work account server (yeah, he needs to clean out his inbox more often), but Mail has repeatedly (I've started fresh several times) downloaded only 1700 messages, stopping with the most recent being June 2007. And, even though he has brand-new messages sitting on that server, whenever I try to get mail, I'm told there are no new messages.
For both of these problems, I've tried everything that's worked for me in the past, tried everything in the Help sections. I logged onto his office work account directly and even tried marking all messages as unread, but Mail still ignores anything new. I would appreciate anyone giving me some help before my husband says again, as he did last night, "Well, at least I have a nice new Mac typewriter."

Answer 1

Gmail POP access has a lot of idiosyncrasies and doesn’t work like a normal POP mail server would. In particular, it doesn’t allow the same message to be downloaded more than once by normal means.
As to the other problem you mention, sometimes messages left on the server clog up the account there, or Mail chokes on a message it cannot download and that prevents it from downloading the rest as well. Solving this problem will probably require removing one or more messages from the server. Except in the case of Gmail (which, as I said, has its own idiosyncrasies), leaving messages on the POP server indefinitely is a bad idea.
You may tell Mail to remove from the server all the messages that have already been downloaded by means of Preferences > Accounts > Advanced > Remove now. Alternatively, you may use the Account Info window to remove specific messages from the server. And if the account allows web access, you may also remove messages from the server that way.
Try removing from the server messages that have already been downloaded and/or the first message not downloaded yet (i.e. the message that Mail appears to be choking on).
You may want to try to download those messages with another mail client such as Thunderbird first, to avoid losing them — and use Eudora Mailbox Cleaner to import them back into Mail afterwards if you wish.