Clearing out PortalAlias table of any extra entries didn't help.

Did a redgate SQL Data Compare on the PortalSettings table and the only records that are different are default skins, favicons, RecordsPerPage etc.

I did notice that there is a DefaultPortalAlias row that was set to localhost on the instance in question, so I changed that to match what the alias should be, but that didn't help either.

 It looks like the PortalSettings table for the working instance has quite a few more rows though..... Wondering if maybe the PortalSettings table for the nonworking instance is incomplete? 

 The working instance has 66 rows for Portal 0 and the non-working has 31 rows for Portal 0

Well after pushing a SQL Data Compare script over to the database and trying to create a child portal, the child portal still exhibits the same issue. Still the same exception as well

DotNetNuke.Services.Exceptions.PageLoadException: The type initializer for 'FormatterGenerator' threw an exception. ---> System.TypeInitializationException: The type initializer for 'FormatterGenerator' threw an exception. ---> System.Web.HttpUnhandledException: Exception of type 'System.Web.HttpUnhandledException' was thrown. ---> System.ArgumentException: SessionPageStatePersister can only be used when enableSessionState is set to true, either in a configuration file or in the Page directive. at System.Web.UI.SessionPageStatePersister..ctor(Page page) at Telerik.Web.UI.RadSessionPageStateCompression.GetStatePersister() at System.Web.UI.Page.get_PageStatePersister() at System.Web.UI.Page.LoadPageStateFromPersistenceMedium() at System.Web.UI.Page.LoadAllState() at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) --- End of inner exception stack trace --- at System.Web.UI.Page.HandleError(Exception e) at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) at System.Web.UI.Page.ProcessRequest(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) at System.Web.UI.Page.ProcessRequest() at System.Web.UI.Page.ProcessRequest(HttpContext context) at System.Web.Mvc.AntiForgeryDataSerializer.FormatterGenerator.TokenPersister.CreateFormatterGenerator() at System.Web.Mvc.AntiForgeryDataSerializer.FormatterGenerator..cctor() --- End of inner exception stack trace --- at System.Web.Mvc.AntiForgeryDataSerializer.get_Formatter() at System.Web.Mvc.AntiForgeryDataSerializer.Serialize(AntiForgeryData token) at System.Web.Mvc.HtmlHelper.GetAntiForgeryTokenAndSetCookie(String salt, String domain, String path) at System.Web.Mvc.HtmlHelper.AntiForgeryToken(String salt, String domain, String path) at DotNetNuke.Framework.ServicesFrameworkImpl.RegisterAjaxAntiForgery(Page page) at DotNetNuke.Framework.PageBase.OnPreRender(EventArgs e) at DotNetNuke.Framework.DefaultPage.OnPreRender(EventArgs evt) in c:\webapps\InCareTraining\Default.aspx.cs:line 759 at System.Web.UI.Control.PreRenderRecursiveInternal() at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) --- End of inner exception stack trace ---