Remote users cannot access POP3

[Guest]

Just recently my users were unable to receive email when they are remote and
using POP3. They get an error that says 0x80042108, unable to connect to
your incoming server. I have looked this error up and found this article
http://support.microsoft.com/default.aspx?scid=kb;en-us;318790
But none of my users are on Norton.

Here is what I have checked so far:
I can ping our mail server by name and get the correct IP addr back (ping
mail.xxx.xxx)
Everyone inside our firewall (Cisco PIX) can receive email fine.
The firewall has the appropriate NAT for the email server.
The firewall is allowing SMTP connection through.

Can someone help me please.

 

[Tyler]

Can any of your users telnet into the mail server?

At a command prompt: "telnet 'mailserver':110". If they can't get
anything that way, it's a firewall issue.

The firewall is allowing SMTP connection through.

your firewall needs to allow POP access as well, so both ports 25 and
110 should be open and forwarded to your server.