Thank you for the response J.A.C.
I agree that having a single VI to do the job of writing to excel for both programs is advantageous.
However, if I were to create an application (i.e. an .exe file) (using the application builder), these two programs would no longer be accessing a shared VI, am i correct? If that is the case, then both .exe programs could access excel simultaneously.
It appears that the easiest way, and most assured way, is to amalgamate both programs into a single program. However, as I mentioned before, this is not the ideal situation. I would like to keep the programs separate.
It would be great to hear more responses. Thank you to everyone who has responded thus far.
Dean.