Why would my Horizontal fluid box be grayed out?

[shannonwaitsBOT]

Started a new Responsive Project

clicked the fluid box 'down arrow' and Horizontal was grayed out.  Vertical was an option.

shannon waits

[Lilybiri]

Which master slide is your slide based on?

[shannonwaitsBOT]

I began with a blank

[Mod Note: Personal Information Removed]

[shannonwaitsBOT]

Oh my goodness…. I got it I got it!

All I needed to do was click Remove fluid boxes.

SO,  a blank project has a fluid box already??

[Mod Note: Personal Information Removed]

[Lilybiri]

You seem to confuse the Blank Theme with a Blank master slide! Because removing the fluid boxes solved your problem, you were not using the Blank master slide which is the only master slide shipping without any Fluid box.

It looks like you had already a fluid box on the used master slide. Maybe this article I wrote recently could clarify some conepts:

Fluid Boxes and Master slides - Captivate blog

I point in this article to an earlier one, about master slides for quizzes:

Tips for 'Fluid' Quiz Slides - Captivate blog

Understanding themes (which include master slides) is one of the basic skills needed for any developer.