Squawk7777
Another neat trick is that you can associate more than one program to a file type, such that you can open it is a variety of different ways. WAV would be a good example, as under some circumstances you might want RealPlayer and Media Player under others.
I have DLLs set up to both register and unregister, for example.
If you, or anyone else, wants to know how I will post instructions.
W