We currently use pop3 accounts with a web mail company for all of our 15 US and UK users. Someone has asked if we could move to exchange. I've never reallygot anywhere close to admin since Outlook 97, and what I was doing then was quite basic. So what are the options? If we hosted our own server it would be on a DMZ of our ADSL line so the US users could access it without using VPN. But I am concerned about the reliability of our connectivity. So if we lost the connection because of a comms or power issue where do the messages go during an outage? Can anyone recommend any good documents on deployment?

If your exchange down, the message will cont. to deliver until time out. (Timing can be set in EMS) Then exchange will generate a NDR (attached undelivered msg) to sender, if NDR cant be delivered to sender, it would sit in BADMAIL. BADMAIL has been disabled in ex2k3 SP1. So, you want to deploy exchange with DMZ. Then use RPC over HTTP instead of VPN, right? Please correct me if theres any misunderstanding. Which version of exchange do you want to use, 03 or 07? Exchange 2003: Here's an article about exchange 03 may guide you: Front-End Server in a Perimeter Network http://technet.microsoft.com/en-us/library/aa996948(EXCHG.65).aspx Also you may need the article about RPC over HTTP for external users instead of VPN: How to configure RPC over HTTP in Exchange Server 2003 http://support.microsoft.com/kb/833401 Exchange 2007: If you want to deploy 07 in your environment, you need to consider which server role you shall put in DMZ. The Edge Transport server role shouldnt in domain and is the only server in DMZ and other roles shall stay internal. Here's an external article about deploying Edge in DMZ Deployment tips for the Exchange 2007 Edge Transport server role http://articles.techrepublic.com.com/5100-10878_11-6187455.html Also how to deploy outlook anywhere (replace 03s RPC over HTTP) http://technet.microsoft.com/en-us/library/aa998934(EXCHG.80).aspx