I'm currently running a SBS 2008 and even tough I configured the size limits in the exchange it is still timing out trying to download massive emails from the isp and the end result is none of the users (big email or not) are getting any emails. Any Ideas??

You need to check who is causing issue to download mail from ISP. Do you see performance issue in SBS server when download it. Event log and perfmon counter will give you idea if you have any issue in system resources. what is WAN bandwidth you have to download mail from ISP. There are several factor which may cause this issue.Anil MCC 2011,ITIL V3,MCSA 2003,MCTS 2010, My Blog : http://messagingschool.wordpress.com

Let me put it like this theres no performance or internet issues have a 4mb Uncapped line, the e-mails download fine aslong as theres no emails larger that 5mb in any of the mailboxes on the isp side, if just one of 48 mailboxes receives a mail larger then 5mb the exchange bombs out, and no one is able to receive emails until that large email has been deleted. The event log gives the following error: Cannot connect to the SMTP server 'localhost' on port 25. The error code was 0x800ccc0f. Verify that the Microsoft Exchange Transport service is running and that the Exchange receive connectors are properly configured

Hello, Do you use POP3 connector to download the emails from ISP? If you are using Exchange receive connector, considering raising the TimeOut value by referring the following article: http://technet.microsoft.com/en-us/library/bb125140(EXCHG.80).aspx Thanks, Simon