Requesting data from Microsoft Exchange Server.  There is no server name listed in the notification.
I have a few users that are reporting they are getting this notification periodically through out the course of their day.  The users that claim this are using both Outlook 2003, and 2000.  Although we also have 2 Outlook 2007 users that aren't experiencing the notification.  The machines they are using are rather old, my guess is at least 5 years old, Pentium 4's with 1GB or less of ram.  The machines are connecting to the Exchange server via our LAN, and they pass through at least 3 switches before reaching the server (6 switches total here).  The last two switches are a logical link dual Cat6 300 foot run. (it's like a long bridge between 5 of the switches and the 6th switch, all the servers are connected to this 6th switch) I"ve been using Cisco Network Analyzer to monitor the bandwidth usage for all the switches and connections and do not see any utilization above even 2% of the 100 mbps or 1000 mbps connections.  I ran a bandwidth monitor on the exchange server and did not log anything in excess of 50 mbps, the NIC in the server is 10/100/1000.  There was some high latency times on the hard disks in the server, but that's the only thing I've come up with as the potential cause.

Could there be any other bottlenecks that are causing this?  The server appears okay except for the hard disks, and the network seems to be handling the bandwidth. Could it just be the older systems that are having problems?  Could it be the length of the cable run?  Some users have a very large in box reaching 2GB and containing 10,000 items and they don't complain, yet others that only have 1GB and 4,000 or less items complain.  

I found the article on how to disable or delay the notification for Outlook 2002, does that apply to 2003 and 2000 as well?  I plan on upgrading all the 2000 users to at least 2003.

Other info: about 24 Exchange users total, MS Windows XP Pro SP2 for all users, Office 2000, 2003 and 2007 in environment.  Mailboxes for 'power' users range from 1GB to 2GB, 4,000 to 15,000 items.  Exchange server has 32GB of total storage space available for storage and is at 17.4 GB full. We also tend to have large data files sent to our FTP server, and most users also access network servers, print servers, and 2 other database servers via this same cat6 logical link)

Thanks.