Exception Details: System.IO.FileNotFoundException: Could not find file "c:inetpubwwwrootDotNetNukeweb.config".
Line 44: ' open the web.config file
Line 45: Dim xmlDoc As New XmlDocument
Line 46: xmlDoc.Load(Common.Globals.ApplicationMapPath & "web.config")
Line 47: Return xmlDoc
Line 48: End Function
This error is simply thrown as there is no web.config file inside the download if you have done whole source download.
This is because there are two other files called development.config and release.config
So the solution is just rename any of these files to web.config and you are done and ready to run your DotNetNuke installation.
If this error in Sitefinity CMS is driving you crazy then there is a simple solution to this problem which is listed below. This error might be caused when there is some missing index folder. WorkAround
Given below are the steps in images which will solve this problem