Where is the email going ?????

I have a client that is running SBS 2000 sp4 and Exchange 2000 (version 6.0.6249:SP3). On the client computers they are running Outlook 2000.
"      They can send email but cannot receive external email. They have no problem with sending or receiving internal email.
"      They use a pop catch all account from an ISP and the POP3 Connector to receive email to there server.
o      Disabled the POP3 connector in SBS
o      Configured outlook express with the correct information to access the catch all email account at the host company.
o      Outlook express can retrieve email from the catchall pop account.
"      I can see this message in the event log when I am using the POP3 Connector:
Event 4023  pop connector
The POP3 session transcript was:
<G>: +OK Hello there.
<C>: USER admin@stellarc.ca
<S>: +OK Password required.
<C>: PASS <secret password>
<S>: +OK logged in.
<C>: STAT
<S>: +OK 12 14626
<C> { Downloaded and deleted messages if necessary. }
<C>: QUIT
<S>: +OK Bye-bye.
"      In the Connector for Pop3 Mailboxes Properties I deleted the Global ISP Mail Hosts account information. Then I ran the SBS Internet Connection Wizard. This wizard asked me to recreate this account which I did. I rebooted the server to see if any of the helped and it did not.
The problem is that the server seems to be receiving email from the ISP but it never shows up in the users inbox. I have checked OWA and the messages do not show up there either.

Does anyone have any ideas on how to fix this problem?