>>I define my form with new dimensions. After that I define (try to) say horizontal scrollable.
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>>After that I try to modify the size of what can be seen when I launch my app.
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>>I cannot grab the side of the form and modify the viewable part of the form so that the scrollbar will appear. I tried with another form and I have the same problem.
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>>Now I'm wondering if there would be a property blocking me.
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>>By the way I did this without in another form.
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>Check ScrollBars property of that Form. If it is equal to 0 (zero) no scrolls will be shown.

It's defined as horizontal.