I have a COM DLL that is invoked from .NET. Already I have registered the COM DLL using regsrv32 in the command prompt.

Now after two months I have got a more recent version of the COM DLL. I want to replace the Old Dll and put this New DLL in its place.

My doubt is: What exact steps I have to take? I am new to COM and I want to be clear before proceeding further ( I do not want any conflicts to occur).

(What I want is NOT side by side execution. I want my code to use the new DLL instead of the old one)

Generally, your best bet is to unregister the original COM, update the file and register the new one. I would advise you to rebuild the COM interop for the DLL. This is most likely easily accomplished by deleting the reference to the library and adding it back in. This will re-run the program that generates the RCW (runtime callable wrapper) interop assembly.

Technically, if the public interfaces on the classes haven't changed you might be able to get away with simply overwriting the DLL file with the update. However, this can be problematic.

Either way you do it, you can not have side-by-side execution of 2 COM libraries with the same name because of the way that COM works.

-Peter
compiledthoughts.com