Why can't I delete slide?

I am trying to delete a slide in Captivate 8 on a Windows 8 computer.
The slide was originally hidden. When I try to show the slide by right clicking the slide, and selecting Show Slide, then clicking delete, it still does not allow me to delete the slide.It goes back to a hidden slide. I get the screen shot above.
I am using this Captivate 8 as a template that was created for me. However, it's NOT a cptm file but a cptx file.
Thanks
