Before Installing DotNetNuke 5.2.2

While checking Linkedin Discussions as my daily routine work, i noticed a Spanish friend's question. His question was about installing DNN 5.2.2 on Windows Server 2008 with IIS7. Well, AFAIK he wasn't new to DotNetNuke so, he was able to install previous versions of DotNetNuke with same certain settings. So it must be something different than permissions.