Simple WinForm ( Not Responding ) Refesh Issue C# 2.0

hello again,


I have a WinForm that can process 100s to 1000s of images.

On the WinForm I have a progress bar, a Label and a Button.

when I click on the process button the progress bar works fine/refreshes
until

If I open a window's explorer window in front of my Form then move it out
of the way, No refresh is happening in my Form ( the progress bar does not
move, but program still working ok)
or
If I move my Form around by dragging it, I get ( Not Responding) in the
title of the Form window

But the Processing continues until the end with no problem.

I have refresh code in my Form inside my Loop where I process a picture
and update my ProgressBar info.

I am not opening any Other Forms or Dialogs. Just one Form only.

do I need to Multi-Thread this one?

what is going on? can someone explain?

Thank you,

OZI



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