XP SP2 with Microsoft outlook

I have windows 2000 domain with exchange 2000 and 30 xp pcs.The client uses
microsoft outlook for the mail.Few of my pc with xp sp2 the mails will not
come automatically once outllook opens.They have to go and click to
Tools-send and receive-Exchange server then mail will come to their inbox,
even the new mail will not come automatically while the outlook keep open
they have to do the same procedure.If i disable the firewall on the sp2 (off)
then mails will come automatically....My scinario is all my clients log in to
the Domain.Microsoft outlook configured with exchange server.

Thnx in advance

In ,
Suresh M V typed:
I have windows 2000 domain with exchange 2000 and 30 xp pcs.The
client uses microsoft outlook for the mail.Few of my pc with xp sp2
the mails will not come automatically once outllook opens.They have
to go and click to Tools-send and receive-Exchange server then mail
will come to their inbox, even the new mail will not come
automatically while the outlook keep open they have to do the same
procedure.If i disable the firewall on the sp2 (off) then mails will
come automatically....My scinario is all my clients log in to the
Domain.Microsoft outlook configured with exchange server.

Thnx in advance

This is because the XP firewall is blocking the inbound UDP packets Exchange
is sending to the client. Set up exceptions in the XP firewall (you should
be able to set up one for the application outlook.exe ) or disable the XP
firewall outright if you don't want it running.