Excel VSTO Add-in error - application domain could not be created

I have an Excel VSTO Add-in that is not installing on one of my users machines. It installs fine on everyone else's machine so far (8 machines), but on this one specific machine it is giving the following error message.

Customization could not be loaded because the application domain could not be created.


************** Exception Text **************
Microsoft.VisualStudio.Tools.Applications.Runtime.CannotCreateCustomizationDomainException: Customization could not be loaded because the application domain could not be created. ---> System.TypeLoadException: Could not load type 'System.AddIn.Pipeline.QualificationDataAttribute' from assembly 'System.AddIn.Contract, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'.
   at System.ModuleHandle.ResolveType(Int32 typeToken, RuntimeTypeHandle* typeInstArgs, Int32 typeInstCount, RuntimeTypeHandle* methodInstArgs, Int32 methodInstCount)
   at System.ModuleHandle.ResolveTypeHandle(Int32 typeToken, RuntimeTypeHandle[] typeInstantiationContext, RuntimeTypeHandle[] methodInstantiationContext)
   at System.Reflection.Module.ResolveType(Int32 metadataToken, Type[] genericTypeArguments, Type[] genericMethodArguments)
   at System.Reflection.CustomAttribute.FilterCustomAttributeRecord(CustomAttributeRecord caRecord, MetadataImport scope, Assembly& lastAptcaOkAssembly, Module decoratedModule, MetadataToken decoratedToken, RuntimeType attributeFilterType, Boolean mustBeInheritable, Object[] attributes, IList derivedAttributes, RuntimeType& attributeType, RuntimeMethodHandle& ctor, Boolean& ctorHasParameters, Boolean& isVarArg)
   at System.Reflection.CustomAttribute.GetCustomAttributes(Module decoratedModule, Int32 decoratedMetadataToken, Int32 pcaCount, RuntimeType attributeFilterType, Boolean mustBeInheritable, IList derivedAttributes)
   at System.Reflection.CustomAttribute.GetCustomAttributes(RuntimeType type, RuntimeType caType, Boolean inherit)
   at System.RuntimeType.GetCustomAttributes(Type attributeType, Boolean inherit)
   at System.Runtime.Remoting.Metadata.RemotingCachedData.GetSoapAttribute()
   at System.Runtime.Remoting.InternalRemotingServices.GetCachedSoapAttribute(Object reflectionObject)
   at System.Runtime.Remoting.SoapServices.GetXmlTypeForInteropType(Type type, String& xmlType, String& xmlTypeNamespace)
   at System.Runtime.Remoting.RemotingServices.DetermineDefaultQualifiedTypeName(Type type)
   at System.Runtime.Remoting.Metadata.RemotingTypeCachedData.get_QualifiedTypeName()
   at System.Runtime.Remoting.Activation.ActivationServices.IsCurrentContextOK(Type serverType, Object[] props, ConstructorCallMessage& ctorCallMsg)
   at System.Runtime.Remoting.Activation.ActivationServices.CreateInstance(Type serverType)
   at System.Runtime.Remoting.Activation.ActivationServices.IsCurrentContextOK(Type serverType, Object[] props, Boolean bNewObj)
   at System.RuntimeMethodHandle._InvokeConstructor(Object[] args, SignatureStruct& signature, IntPtr declaringType)
   at System.RuntimeMethodHandle.InvokeConstructor(Object[] args, SignatureStruct signature, RuntimeTypeHandle declaringType)
   at System.Reflection.RuntimeConstructorInfo.Invoke(BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
   at Microsoft.VisualStudio.Tools.Office.Runtime.DomainCreator.DomainInitializer.ActivatePipeline(String addInAssembly, String addInClass, String[] pipelineInfo)
   at Microsoft.VisualStudio.Tools.Office.Runtime.DomainCreator.DomainInitializer.StartAddIn(IntPtr hostServiceProvider, String[] pipeline, String assemblyName, String[] entryPoints)
   at Microsoft.VisualStudio.Tools.Office.Runtime.DomainCreator.DomainInitializer.StartAddIn(IntPtr hostServiceProvider, String[] pipeline, String assemblyName, String[] entryPoints)
   at Microsoft.VisualStudio.Tools.Office.Runtime.DomainCreator.LoadMafPipeline(AppDomain newDomain, IntPtr hostServiceProvider, String fullAssemblyName, String[] entryPoints, OfficeApp officeApplication, OfficeVersion officeVersion, IntPtr& executor)
   at Microsoft.VisualStudio.Tools.Office.Runtime.DomainCreator.CreateCustomizationDomainInternal(String solutionLocation, String manifestName, String documentName, Boolean showUIDuringDeployment, IntPtr hostServiceProvider, Boolean useFastPath, IntPtr& executor)
   --- End of inner exception stack trace ---


************** Loaded Assemblies **************
mscorlib
    Assembly Version: 2.0.0.0
    Win32 Version: 2.0.50727.5456 (Win7SP1GDR.050727-5400)
    CodeBase: file:///C:/Windows/Microsoft.NET/Framework/v2.0.50727/mscorlib.dll
----------------------------------------
Microsoft.VisualStudio.Tools.Office.Runtime.v10.0
    Assembly Version: 10.0.0.0
    Win32 Version: 10.0.31007.0
    CodeBase: file:///C:/Windows/assembly/GAC_MSIL/Microsoft.VisualStudio.Tools.Office.Runtime.v10.0/10.0.0.0__b03f5f7f11d50a3a/Microsoft.VisualStudio.Tools.Office.Runtime.v10.0.dll
----------------------------------------
System
    Assembly Version: 2.0.0.0
    Win32 Version: 2.0.50727.5456 (Win7SP1GDR.050727-5400)
    CodeBase: file:///C:/Windows/assembly/GAC_MSIL/System/2.0.0.0__b77a5c561934e089/System.dll
----------------------------------------
System.Core
    Assembly Version: 3.5.0.0
    Win32 Version: 3.5.30729.5420 built by: Win7SP1
    CodeBase: file:///C:/Windows/assembly/GAC_MSIL/System.Core/3.5.0.0__b77a5c561934e089/System.Core.dll
----------------------------------------
Microsoft.VisualStudio.Tools.Applications.Hosting.v10.0
    Assembly Version: 10.0.0.0
    Win32 Version: 10.0.31007.0
    CodeBase: file:///C:/Windows/assembly/GAC_MSIL/Microsoft.VisualStudio.Tools.Applications.Hosting.v10.0/10.0.0.0__b03f5f7f11d50a3a/Microsoft.VisualStudio.Tools.Applications.Hosting.v10.0.dll
----------------------------------------
System.AddIn
    Assembly Version: 3.5.0.0
    Win32 Version: 3.5.30729.5446 built by: Win7SP1GDR
    CodeBase: file:///C:/Windows/assembly/GAC_MSIL/System.AddIn/3.5.0.0__b77a5c561934e089/System.AddIn.dll
----------------------------------------
Microsoft.VisualStudio.Tools.Applications.ServerDocument.v10.0
    Assembly Version: 10.0.0.0
    Win32 Version: 10.0.31007.0
    CodeBase: file:///C:/Windows/assembly/GAC_MSIL/Microsoft.VisualStudio.Tools.Applications.ServerDocument.v10.0/10.0.0.0__b03f5f7f11d50a3a/Microsoft.VisualStudio.Tools.Applications.ServerDocument.v10.0.dll
----------------------------------------
Microsoft.VisualStudio.Tools.Applications.Runtime.v9.0
    Assembly Version: 9.0.0.0
    Win32 Version: 9.0.30729.4130
    CodeBase: file:///C:/Windows/assembly/GAC_MSIL/Microsoft.VisualStudio.Tools.Applications.Runtime.v9.0/9.0.0.0__b03f5f7f11d50a3a/Microsoft.VisualStudio.Tools.Applications.Runtime.v9.0.dll
----------------------------------------

I am not sure why I would be getting this error. From googling' around, nothing was returned from a respectable source. I had the user validate that .NET 3.5 was installed, ran it as administrator, but nothing seems to help.

I have an installer that automatically hooks the add-in to excel from the registry, but if the VSTO is installed, the same error message occurs.

I can't understand what this error message is telling me. Can anyone help me out?

On Windows 7 64-bit, we had a similar issue. Some of the referencing errors were:

Not loaded. A runtime error occurred during the loading of the COM Add-in.

Microsoft.VisualStudio.Tools.Applications.Runtime.CannotCreateCustomizationDomainException: Customization could not be loaded because the application domain could not be created.

System.TypeLoadException: Could not load type 'System.AddIn.Pipeline.QualificationDataAttribute' from assembly 'System.AddIn.Contract, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'.

This issue was caused by corruption in Microsoft .NET Framework 3.5.1, which is a feature of the operating system.

How to Repair or Reinstall .NET Framework 3.5 http://www.adminarsenal.com/admin-arsenal-blog/how-to-repair-or-reinstall-net-framework-3-5/

This post claims that the full .NET framework (as opposed to the client profile) must be installed when encountering this exception. Several people state that this fixed the problem for them.

(Ideally your VSTO should only require the client profile framework. Are you doing something in your VSTO that requires the full framework, or is that one of the prerequisites?)

Ok - well turns out it was something wrong with the users machine. Had the user uninstall my add-in and enable other ones on his machine and the error message still appeared. Time to troubleshoot him machine instead of my add-in!

As a note for other people, you can see the error messages by unsuppressing error messages from adding a variable into Environment Variables -> System Variables