So I had a site that was running 05.04.04. I went through the recommended upgrade path 5.06.08, 6.02.08 and finally 7.02.03. Everything went fine until I got 7.02.03. I can get to the login screen, but when I login I get an error that points to Fujitsu.Cobol. I've searched around and can't find anything pointing to a similar problem. I have no idea what the reference is from. It's not in my web.config. Here's the error. Any help would be greatly appreciated.

[Thread:16][ERROR] DotNetNuke.Services.Exceptions.Exceptions - DotNetNuke.Services.Exceptions.PageLoadException: Exception has been thrown by the target of an invocation. ---> System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.TypeInitializationException: The type initializer for 'DotNetNuke.ExtensionPoints.ExtensionPointManager' threw an exception. ---> System.IO.FileNotFoundException: Could not load file or assembly 'Fujitsu.COBOL, Version=3.1.110.0, Culture=neutral, PublicKeyToken=fac0fe3cab973246' or one of its dependencies. The system cannot find the file specified.

at System.ModuleHandle.ResolveType(RuntimeModule module, Int32 typeToken, IntPtr* typeInstArgs, Int32 typeInstCount, IntPtr* methodInstArgs, Int32 methodInstCount, ObjectHandleOnStack type)

at System.ModuleHandle.ResolveTypeHandleInternal(RuntimeModule module, Int32 typeToken, RuntimeTypeHandle[] typeInstantiationContext, RuntimeTypeHandle[] methodInstantiationContext)

at System.Reflection.RuntimeModule.ResolveType(Int32 metadataToken, Type[] genericTypeArguments, Type[] genericMethodArguments)

at System.Reflection.CustomAttribute.FilterCustomAttributeRecord(CustomAttributeRecord caRecord, MetadataImport scope, Assembly& lastAptcaOkAssembly, RuntimeModule decoratedModule, MetadataToken decoratedToken, RuntimeType attributeFilterType, Boolean mustBeInheritable, Object[] attributes, IList derivedAttributes, RuntimeType& attributeType, IRuntimeMethodInfo& ctor, Boolean& ctorHasParameters, Boolean& isVarArg)

at System.Reflection.CustomAttribute.IsCustomAttributeDefined(RuntimeModule decoratedModule, Int32 decoratedMetadataToken, RuntimeType attributeFilterType, Int32 attributeCtorToken, Boolean mustBeInheritable)

at System.Reflection.CustomAttribute.IsDefined(RuntimeType type, RuntimeType caType, Boolean inherit)

at System.RuntimeType.IsDefined(Type attributeType, Boolean inherit)

at System.ComponentModel.Composition.AttributedModel.AttributedPartCreationInfo.IsPartDiscoverable()

at System.ComponentModel.Composition.AttributedModel.AttributedModelDiscovery.CreatePartDefinitionIfDiscoverable(Type type, ICompositionElement origin)

at System.ComponentModel.Composition.Hosting.TypeCatalog.get_PartsInternal()

at System.ComponentModel.Composition.Hosting.TypeCatalog.GetEnumerator()

at System.ComponentModel.Composition.Hosting.AssemblyCatalog.GetEnumerator()

at System.Linq.EnumerableQuery`1.GetEnumerator()

at System.Linq.EnumerableQuery`1.System.Collections.Generic.IEnumerable<T>.GetEnumerator()

at System.Collections.Generic.List`1..ctor(IEnumerable`1 collection)

at System.Linq.Enumerable.ToList[TSource](IEnumerable`1 source)

at DotNetNuke.ExtensionPoints.SafeDirectoryCatalog..ctor(String directory)

at DotNetNuke.ExtensionPoints.ExtensionPointManager.InitializeMefCompositionContainer()

at DotNetNuke.ExtensionPoints.ExtensionPointManager..cctor()

--- End of inner exception stack trace ---

at DotNetNuke.ExtensionPoints.ExtensionPointManager.ComposeParts(Object[] attributeParts)

at DotNetNuke.ExtensionPoints.ExtensionPointManager..ctor()

at DotNetNuke.Web.Components.Controllers.ControlBarController..ctor()

--- End of inner exception stack trace ---

at System.RuntimeTypeHandle.CreateInstance(RuntimeType type, Boolean publicOnly, Boolean noCheck, Boolean& canBeCached, RuntimeMethodHandleInternal& ctor, Boolean& bNeedSecurityCheck)

at System.RuntimeType.CreateInstanceSlow(Boolean publicOnly, Boolean skipCheckThis, Boolean fillCache, StackCrawlMark& stackMark)

at System.RuntimeType.CreateInstanceDefaultCtor(Boolean publicOnly, Boolean skipCheckThis, Boolean fillCache, StackCrawlMark& stackMark)

at System.Activator.CreateInstance[T]()

at DotNetNuke.Framework.ServiceLocator`2.InitInstance()

at System.Lazy`1.CreateValue()

--- End of stack trace from previous location where exception was thrown ---

at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()

at System.Lazy`1.get_Value()

at DotNetNuke.Framework.ServiceLocator`2.get_Instance()

at DotNetNuke.UI.ControlPanels.ControlBar.LoadCustomMenuItems()

at DotNetNuke.UI.ControlPanels.ControlBar.OnInit(EventArgs e)

at System.Web.UI.Control.InitRecursive(Control namingContainer)

at System.Web.UI.Control.AddedControl(Control control, Int32 index)

at System.Web.UI.ControlCollection.AddAt(Int32 index, Control child)

at DotNetNuke.UI.Skins.Skin.InjectControlPanel()

at DotNetNuke.UI.Skins.Skin.OnInit(EventArgs e)

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.Framework.DefaultPage.OnInit(EventArgs e)

at System.Web.UI.Control.InitRecursive(Control namingContainer)

at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)

--- End of inner exception stack trace ---

Thanks Sebastian - Your intuition was correct.  It turns our that it was an old module that was causing the problem.  I started removing dlls from the bin directory and found the offender.  It looks like older versions of DNN didn't immediately throw an error when initially loading the site because I believe that the errors were occurring even though they weren't apparent. 

I appreciate your help.