I'm having a recurring problem which renders a .Net dll useless to the
COM clients I am distributing the dll to.

The .Net dll has been defined in all of the proper ways.  At the
assmbly level, I hardcode (with attributes) the GUID of the library
and the version of the library, as well as specifying that all classes
should not be COM visible by default.  I mark (again with attributes)
each class to be exported with a valid GUID as well as specifying that
the class is COM visible and not to generate a COM interface.  Instead
of generating the COM interfaces via tlbexp, I create the interfaces
myself, marking them with a valid GUID and as COM visible.  The
exported classes then implement the defined interfaces.

Also, I created a valid secrutiy key file and set my assembly to use
the key file with an attribute in the Assembly.cs file.

To compile the assembly, I use the Visual Studio Development
environment which places the resulting dll in the bin\Debug directory
of my project home. Then, from the command line, I issue the following
two commands:

regasm /codebase MyAssembly.dll
tlbexp MyAssembly.dll

Then, in a separate project, I try to import the .tlb file and
instance a class in the assembly using early binding.  Basically it
looks like this:

#import "mscorlib.tlb" rename("ReportEvent", "dotNetReportEvent")
#import "C:\\ThePathToMyDebugDir\\MyAssembly.tlb" no_namespace
named_guids

int _tmain(int argc, _TCHAR* argv[])
{
   CoInitialize(NULL);

   IMyClass1Ptr myClassInstance(__uuidof(MyClass1));

   IMyClass2Ptr anotherInstance;
   try
   {
       anotherInstance= myClassInstance->CreateAnObject("aParam");
   }
   catch (_com_error e)
   {
       printf("Dang!");
   }
}

I compile this code, and run it in debug mode.  It works. All is well
with the world.

Now, I decide that I want to change the location of the assembly on my
system (or I want to change some interfaces, etc. There are a variety
of circumstances that cause this to fail).  So I do the following
things:

1.  I copy the assembly dll to a new location.
2. I run 'regasm /u MyAssembly.dll' from the Debug directory to
unregister the types in my Assembly.
3. I cd to the new location of my assembly.
4. I run 'regasm /codebase MyAssembly.dll' to register the dll in the
new location.

Note that I did NOT recompile the .Net assembly.  I just copied it to
a new location.  Now I try running my C++ COM code again.  This time,
it gets to the line with: 'anotherInstance=
myClassInstance->CreateAnObject("aParam");' and COM throws an
exception stating: '0x80070002 The system cannot find the file
specified.'

At this point, no matter what I do, I cannot get the assembly to work
with my C++ COM client at its new location.

However, if I unregister the dll at its new location, then register
the dll at its original location (the Debug directory of the .Net
Assembly's project) the C++ COM client will often (though not always)
work again.

This has me stumped.  I've looked throught the registry and everything
looks fine.  But I suspect that SOME entry is not getting properly
deleted or added during the process of registering and unregistering
the .Net assembly.

Any thoughts or similar experiences on this subject would be greatly
appreciated.

Taft