Can Exchange 2007 and SQL 2008 run on Windows Server 2008 at the same time? IF not, how does Windows Small Business Server 2008 have both, what files and directories were added to make them work together ?

Yes they both can work but Microsoft doesnt recommends becasue Running SQL Server on the same computer as a production Exchange mailbox server is not recommended. Both SQL Server and Exchange mailbox servers consume a large amount of memory and disk resources to operate optimally. Co-hosting SQL Server and Exchange Server on the same computer in a production environment will likely lead to poor performance by one or both of the servers. Additionally, troubleshooting and securing such an installation is not well understood. Finally, there are a number of known interoperability issues that you may encounter if you are running SQL Server and Exchange Server on the same computer. Most of these issues are the result of version inconsistencies with files or programs common to the two servers, such as Microsoft Distributed Transaction Coordinator (MS DTC), Microsoft ActiveX® Data Objects (ADO), and OLE Database (OLE DB). IF not, how does Windows Small Business Server 2008 have both, what files and directories were added to make them work together Its architecture is designed to do that http://www.virmansec.com/blogs/skhairuddin

AFAIK, running SQL Server with Exchange on the same server is not recommanded. Both SQL and Exchange Server comsume a large amount of memory and disk resources which will lead to poor performance. Also, troubleshooting and securing such an install is not more difficult. For more information, post in the SQL and Exchange forums. For SBS questions, post in the SBS forum. I found this link that confirm what I said. This posting is provided "AS IS" with no warranties or guarantees , and confers no rights. Microsoft Student Partner Microsoft Certified Professional Microsoft Certified Systems Administrator: Security Microsoft Certified Systems Engineer: Security Microsoft Certified Technology Specialist: Windows Server 2008 Active Directory, Configuration Microsoft Certified Technology Specialist: Windows Server 2008 Network Infrastructure, Configuration