I've just installed a new Server 2008 domain on a small SOHO office.
Employee's frequently, almost 90% of the time, encounter problems receiving from the pop3 server and less frequently sending via the smtp server.
1: When I first installed outlook on all the clients and set up their email accounts and sync'd their PST files off the server there was no issue receiving mail.
2: It does not matter if this is a workstation joined to the domain or a unmanaged laptop operating off the wireless network.
3: The issue is present in both Microsoft Outlook 2007 and Mozilla Thunderbird for Mac
I'm thinking the issue might be the Cisco 877 router, but I'm not Cisco cert'd and could use a little direction if you believe this is the issue as well......