How to install Exchange Server 2007 SP2 on SBS 2008

There is an issue with installing SP2 for Exchange 2007 on SBS 2008, Microsoft has released a tool to get passed the errors – link. You need to download and extract Exchange 2007 SP2 – link, run the install tool. It will ask for the directory of SP2, and then you install SP2 normally.

Here are more details of the issue on MSExchange.org