EOF on socket when opening pop3 inbox

Question

I have a Java program that reads a pop3 inbox and sends appropriate response emails. The program was working fine but something somewhere changed and now I get the following Exception:
Exception in thread "main" javax.mail.MessagingException: Open failed;
  nested exception is:
     java.io.EOFException: EOF on socket
     at com.sun.mail.pop3.POP3Folder.open(POP3Folder.java:215)I wrote a simple Class to reproduce the error:
    private void execute() throws MessagingException {
        Properties props = new Properties();
        props.put("mail.smtp.host", "mail.smtp.host");
        props.put("mail.store.protocol", "pop3");
        // Session session = Session.getInstance(props, null);
        Session session = Session.getDefaultInstance(props);
        Store store = session.getStore("pop3");
        store.connect("mail.myDomain.com", "myUser", "myPassword");
        Folder inbox = store.getFolder("INBOX");
        inbox.open(Folder.READ_ONLY);
    }It connects to the store okay. The exception is thrown at the the line with store.getFolder("INBOX"). I've checked our firewall settings and email server settings (dovecot/postfix) and all seems well.
Anyone have a clue what this might be?

Answer 1

Thanks for your quick reply.
Here's the trace:
DEBUG: setDebug: JavaMail version 1.4.5
DEBUG: getProvider() returning javax.mail.Provider[STORE,pop3,com.sun.mail.pop3.POP3Store,Sun Microsystems, Inc]
DEBUG POP3: mail.pop3.rsetbeforequit: false
DEBUG POP3: mail.pop3.disabletop: false
DEBUG POP3: mail.pop3.forgettopheaders: false
DEBUG POP3: mail.pop3.cachewriteto: false
DEBUG POP3: mail.pop3.filecache.enable: false
DEBUG POP3: mail.pop3.keepmessagecontent: false
DEBUG POP3: mail.pop3.starttls.enable: false
DEBUG POP3: mail.pop3.starttls.required: false
DEBUG POP3: mail.pop3.apop.enable: false
DEBUG POP3: mail.pop3.disablecapa: false
DEBUG POP3: connecting to host "mail.myDomain.com", port 110, isSSL false
S: +OK Dovecot ready.
C: CAPA
S: +OK
CAPA
TOP
UIDL
RESP-CODES
PIPELINING
STLS
USER
SASL PLAIN
DEBUG POP3: PIPELINING enabled
DEBUG POP3: authentication command trace suppressed
DEBUG POP3: authentication command succeeded
C: STAT
S: EOF
C: QUIT
S: EOF
Exception in thread "main" javax.mail.MessagingException: Open failed;
  nested exception is:
     java.io.EOFException: EOF on socket
     at com.sun.mail.pop3.POP3Folder.open(POP3Folder.java:228)
     at com.myTest.TestOpenInbox.execute(TestOpenInbox.java:26)
     at com.myTest.TestOpenInbox.main(TestOpenInbox.java:13)
Caused by: java.io.EOFException: EOF on socket
     at com.sun.mail.pop3.Protocol.readResponse(Protocol.java:742)
     at com.sun.mail.pop3.Protocol.simpleCommand(Protocol.java:687)
     at com.sun.mail.pop3.Protocol.stat(Protocol.java:354)
     at com.sun.mail.pop3.POP3Folder.open(POP3Folder.java:203)
     ... 2 moreIt's Greek to me, but it appears everything is kosher until C:STAT S:EOF