Autofac throws exception for Microsoft.Office.Interop.Word.Application

The following code in VSTO Add-in for Word works on my machine when I run it as Administrator or User:
using Autofac;
using Word = Microsoft.Office.Interop.Word;
namespace ComObjectIssue
{
//...
var builder = new ContainerBuilder();
var wordApp = Globals.ThisAddIn.Application;
builder.RegisterInstance(Globals.ThisAddIn.Application).SingleInstance();
builder.RegisterType<TodayWriter>().As<IDateWriter>();
Container = builder.Build(); // throws "System.ArgumentException: The type 'System.__ComObject' is not assignable to service 'Microsoft.Office.Interop.Word.Application'." when customer runs it as User
using (var scope = Container.BeginLifetimeScope())
{
var writer = scope.Resolve<IDateWriter>();
writer.WriteDate();
}
//...
public interface IDateWriter
{
void WriteDate();
}
public class TodayWriter : IDateWriter
{
private readonly Word.Application wordApp;
public TodayWriter(Word.Application wordApp)
{
this.wordApp = wordApp;
}
public void WriteDate()
{
//...
}
}
}
But for one of our customers, it works only if he runs it as Administrator — if MS Word is running as User, Autofac's container build method throws an exception:
System.ArgumentException: The type 'System.__ComObject' is not assignable to service 'Microsoft.Office.Interop.Word.Application'.
at Autofac.Builder.RegistrationBuilder.CreateRegistration(Guid id, RegistrationData data, IInstanceActivator activator, IResolvePipelineBuilder pipelineBuilder, Service[] services, IComponentRegistration target)
at Autofac.Builder.RegistrationBuilder.CreateRegistration[TLimit,TActivatorData,TSingleRegistrationStyle](IRegistrationBuilder3 builder) at Autofac.Builder.RegistrationBuilder.RegisterSingleComponent[TLimit,TActivatorData,TSingleRegistrationStyle](IComponentRegistryBuilder cr, IRegistrationBuilder
3 builder)
at Autofac.ContainerBuilder.Build(IComponentRegistryBuilder componentRegistry, Boolean excludeDefaultModules)
at Autofac.ContainerBuilder.Build(ContainerBuildOptions options)
As I mentioned above, on my computer it works for both Administrator and User. What kind of security policy on customer machines can be the cause of this issue?
I posted a similar question on StackOverflow — Autofac cannot resolve Microsoft.Office.Interop.Word.Application, made some experiments with GAC and Microsoft Visual Studio 2010 Tools for Office Runtime. It did not help.