VB6 DLL failing to unregister

Hi there

I have a .NET application which uses some VB6.0 dlls.

Of late, I've noticed that when I uninstall my application, there's a particular dll that remains, such that I have to manually unregister and then delete before I can do another installation.

I can't think of anything I've done to cause this, nor can I think of how to resolve it. This is going to cause problems for the user.

Any ideas will be welcome.

Thanks

Is it possible that the DLL is a newer version of an old one, and existing programs on that PC are using it?

If so then its probably best to leave the DLL installed.

Yes, it's a newer version of an old one. But this dll is always being updated such that the version keeps changing.

All the user will do when they want to install a newer version of the .NET application is uninstall the existing one, then install the new one, unaware that one dll didn't unregister.

So the old version remains, and when trying to use the application, it will come up with error 430 "Class does not support automation ..."