is fmViewer an array? or are you trying to do something else....please
explain a little bit more

What is frmViewer?  Here you are using it as both the name of your
class and the name of the array variable.  Can you show us the
declaration for frmViewer?

Chris

Jerry,

All Form access must be done from the main UI thread.  That includes
creating, manipulating, and showing the Form.  You'll need a reference
to an existing Form or Control that your worker thread will use to
marshal the execution of a delegate onto the UI thread by calling
Invoke or BeginInvoke.  That delegate should contain the code to create
and show the new Form.  Invoke and BeginInvoke are among the very few
members of a Form or Control that are actually thread-safe.

Brian