#1 can't exit program

[Anonymous]

program works fine, but when attempting to exit the following message appears:

DEBUG: Closing
EXCEPTION: Value cannot be null.
Parameter name: Value cannot be null

also, when the dg-100 is accessed the status graph (com 7) reaches full but doesn't clear

xpsp3, .net 2.0, and nis 2009, since I have to use task manager to kill the program, I can't use the gmouse function and setting aren't saved

any ideas?
kabiggs@suddenlink.net