问题
For some reason, whenever I'm reading all emails via POP3 Gmail I can only ever receive the first 290 emails! These date back to 2004 and are of little use.
Is there a way to either specify a date range to receive or actually receive them all? I've tried using many different POP3 libraries and got no further, they all receive the same amount of emails.
Although commercial products would be nice, I can't afford them right now so please no suggestions to use the many brilliant commercial POP3 clients.
Thnaks, Daniel.
回答1:
i think google have some problems with pop3 event with outlook , the program downloaded the mails two times . my work around was connecting with IMAP its batter protocol and have more advanced options and google support it , now i try to find good .net IMAP library . if you managed to get pop3 work with gmail please till us.
回答2:
For some reason, GMail does this. I have found that if you apprent the string "recent:" before your user name when sending the USER message, you get more messages, and the most recent (last 30 days).
回答3:
There's nothing in the POP3 protocol to support retrieving by date, or forcing all messages. The STAT command should tell you how many, and then the LIST command should list them all.
Can you trace the traffic (using Wireshark if necessary) and see what the responses fromn google are? Particularly interesting would be the response to the STAT command:
[STAT] The positive response consists of "+OK" followed by a single space, the number of messages in the maildrop, a single space, and the size of the maildrop in octets.
[LIST] If no argument was given and the POP3 server issues a positive response, then the response given is multi-line. After the initial +OK, for each message in the maildrop, the POP3 server responds with a line containing information for that message.
来源：https://stackoverflow.com/questions/4245143/problem-reading-all-gmail-emails-via-pop3-can-only-ever-get-first-290