Cathal,

I modified my web.config file based on the development.config.file.  Now my errors are as follows:

Error: Event Viewer is currently unavailable.
DotNetNuke.Services.Exceptions.ModuleLoadException: The type initializer for 'DotNetNuke.Services.Log.EventLog.LoggingProvider' threw an exception. ---> System.TypeInitializationException: The type initializer for 'DotNetNuke.Services.Log.EventLog.LoggingProvider' threw an exception. ---> System.NullReferenceException: Object reference not set to an instance of an object. at DotNetNuke.Framework.Reflection.CreateObject(String ObjectProviderType, String ObjectProviderName, String ObjectNamespace, String ObjectAssemblyName, Boolean UseCache) at DotNetNuke.Services.Log.EventLog.LoggingProvider.CreateProvider() at DotNetNuke.Services.Log.EventLog.LoggingProvider..cctor() --- End of inner exception stack trace --- at DotNetNuke.Services.Log.EventLog.LogController.AddLog(LogInfo objLogInfo) --- End of inner exception stack trace ---

Unhandled error loading module.
DotNetNuke.Services.Exceptions.ModuleLoadException: Unhandled Error Adding Module to ContentPane ---> System.TypeInitializationException: The type initializer for 'DotNetNuke.Services.Log.EventLog.LoggingProvider' threw an exception. ---> System.NullReferenceException: Object reference not set to an instance of an object. at DotNetNuke.Framework.Reflection.CreateObject(String ObjectProviderType, String ObjectProviderName, String ObjectNamespace, String ObjectAssemblyName, Boolean UseCache) at DotNetNuke.Services.Log.EventLog.LoggingProvider.CreateProvider() at DotNetNuke.Services.Log.EventLog.LoggingProvider..cctor() --- End of inner exception stack trace --- at DotNetNuke.Services.Log.EventLog.LogController.GetLogTypeInfo() at DotNetNuke.Modules.Admin.Log.LogViewer.Page_Init(Object sender, EventArgs e) at System.Web.UI.Control.OnInit(EventArgs e) at System.Web.UI.UserControl.OnInit(EventArgs e) at System.Web.UI.Control.InitRecursive(Control namingContainer) at System.Web.UI.Control.InitRecursive(Control namingContainer) at System.Web.UI.Control.InitRecursive(Control namingContainer) at System.Web.UI.Control.InitRecursive(Control namingContainer) at System.Web.UI.Control.InitRecursive(Control namingContainer) at System.Web.UI.Control.InitRecursive(Control namingContainer) at System.Web.UI.Control.AddedControl(Control control, Int32 index) at System.Web.UI.ControlCollection.Add(Control child) at DotNetNuke.UI.Skins.Skin.InjectModule(Control objPane, ModuleInfo objModule, PortalSettings PortalSettings) --- End of inner exception stack trace ---

Can I suggest that you look at what dotnetnuke.* files you have in your installation?  because you upgraded from 3.x to 4.8.x, you've probably still got a lot of httphandler dlls from back when the handlers were all separate DLLs.  You might want to archive all the dotnetnuke.* files from your bin directory, then copy in the new 4.8.x versions.   You'll need to keep any module-specific versions.

That's what I would expect from your problem - the type initialiser is picking up the wrong DLL version, and matching perhaps the namespace but not the DLL name.

Just a guess though!