Shortcut key Pagedown doesn't work

[PeterS]

Hello all,
we have a problem with the shortcut key "Page down".
In our Display we have grids with scrollbar and "next page" item. All works. If we scroll down, we can go back with page up.
But we can not scroll down with page down-key.

So even if i do a button with a function, and I put this button with shortcut key "page down" it doesn't work. - If I change the shortcut key for example to F10 it works.

I really do not have any idea what's the matter.

If anybody can give me a hint it would be fine.

Thanks
Peter
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