From my PC, I sent an email from 1 account on my server (RAQ 4i) to another account also on my server at about 10:30 yesterday(9/14) and I did not receive the email until 6:35 PM today (9/15). I have had a customer complain about slow email delivery for interoffice emails (within same domain) citing the same problem (email does not get delivered until next day). I know this is a very general question, but what kind of things can I look at on my server to attempt to track/resolve this problem? Could the ISP cause a delay (even if I am using the RAQ mail server to send/receive)? Could my customer have better luck if he uses the outgoing mail server of his ISP? We are all using Outlook/Outlook Express.

one thing worth trying would be the updated qpopper package available from solarspeed:
http://www.solarspeed.net/index.php?topic=downloads&menu=0

You might want to check the mail queues as well and if there are a lot of messages there flush them and restart sendmail.

I had a client once who set up his dns not quite well that took it also into a slow mailrespons. So perhaps it is handy to check your DNS aswell.


HTH :D