Required .NET hosting and if you are planning to utilize a Shared Hosting account for this, you may see some performance issues. At least this was the case when I used DNN about 2.5 years ago. I loved it, every feature of it but the lack of templates back then and the fact that my host's configuration put site processes such as the MSSQL instance, to sleep made it not worth the pain. There were cache and query utilities to prevent this but it was not worth it for me.
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