Can Send but not Recieve

[Guest]

I have read through lots of past posts, but can't get any idea from them. We
are running Outlook 2003 on all (6) desktops in the office. There is one
desktop that is designated as the 'server'; all the computers connect through
a router to this machine. Last week, we stopped being able to recieve
e-mails in Outlook. Sent mail goes out fine, but there are no e-mails coming
in. No error messages are shown. When I try and send an e-mail from my
personal e-mail to my office, nothing happens, and the next day I get this
message in my Yahoo! inbox:

Sorry, I wasn't able to establish an SMTP connection. (#4.4.1)
I'm not going to try again; this message has been in the queue too long.

We are running Norton Corporate antivirus; I can't seem to find a way to
disable the incoming to see if that is the problem. Thanks for your help.

 

[Guest]

The NDR error explanation for 4.1.1 is:
Intermittent network connection. The server has not yet responded. Classic
temporary problem. If it persists, you will also a 5.4.x status code error.
Was anything changed on that computer? Any patches applied, software
installed, anything at all?

 

[Guest]

The only thing that that I vaguely remember around that time wa an automatic
update from Microsoft, but I don't think it was on the day (last wednesday)
that the e-mail stopped working. Other than that, nothing. Our Norton is
set for LiveUpdate, so I suppose it could have done something then, but not
that I can tell. The 'server' that outlook uses is running windows 2000; i
don't think it has the restore function of XP, though it might be nice.