worksheet selection change
 

I have a subroutine that I would like to run when any cell on a
worksheet changes. I can run the subroutine without a problem by
adding a button to the worksheet and pointing it to that particular
macro. but when I try to add the worksheet change event I am getting
errors. It seems to be a problem with an addin that solved cubic
equations. whenever the sub is called from the worksheet change event,
the results are #value which causes an error. I don't understand
what the difference is if I run the macro from a button or a change
event. any ideas?

thanks,
Jacob