Another issue that I had before I got the Exchange 2010 installed and working on my Windows Server 2008 R2 Enterprise edition was that it would keep giving me an error saying cannot access default website.
After making sure that all prerequisites for installing Exchange 2010 was met (like installing IIS, .NET etc) I proceeded to install the Exchange server, but it will fail every-time with an error saying it cannot access the default website, make sure IIS was properly installed and stuff. Even reinstalling the IIS would not make it happy and it wouldn’t let me go any further. Finally after doing some research and looking at logs, it seemed like the Exchange server was also looking for IIS 6.0 management compatibility role services (which by the way is additional role service that can be added even after IIS installation). After adding that role services (and make sure that you have application server installed, not just .NET) I started Exchange server install wizard and this time it surely passed all the tests and it was a go.
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