Unfortunately the steps taken were not documented, these lessons learnt are therefore from memory and may not accurately reflect what happened.
For reference, DNN 9 Community Edition is installed through an IIS WebPI (Web Platform Installer) and seems to only use SQL Express. No luck has been had using an existing SQL Server installation that exists on the same machine.
*Update 2017-05: The above paragraph is incorrect. The install files for the Community Edition can be downloaded from here http://www.dnnsoftware.com/community/download
Installing DNN 9 Community Edition on Windows Server 2016 Datacenter
NO DICE. Countless errors were encountered and the DNN 9 site created in IIS was unusable.
Installing DNN 9 Community Edition on Windows Server 2012 Datacenter R2
NO DICE on the first attempt. The server I built only had Windows Server 2012 Datacenter R2 installed with no updates applied. All ASP.NET and IIS related Features / Roles were activated.
I’m unsure of the actual final result of this test. On reflection, perhaps there were missing DLL’s that couldn’t be loaded resulting in the DNN 9 Wizard Installer failing.
Installing DNN 9 Community Edition on Windows Server 2012 Datacenter R2, round two.
A new server was built and Windows Server 2012 Datacenter R2 was installed. All ASP.NET and IIS Features were activated before beginning a lengthy update cycle to bring the server up to date. It’s believed that this was the critical step missing previously.
DNN 9 Community edition was then installed through IIS WebPI. There was an error when installing – “…/Installer/InstallWizard.aspx.cs does not exist”. The workaround was to manually navigate to <install url>/installer/install.aspx and continue with the installation. This worked fine.
Our only problem since then has been the flakiness of SQL Server Express 2008. It has required a daily restart to bring our installation of DNN 9 Community edition back online.