No, the font size is pulled from the system font size. This is set by the
system, not the presentation.
Start => Control Panel => Display => Appearance => Advanced => Message Box
=> Font settings
However, there is no reason that you can not create your own 'faux message
box' using User Forms in VBA.

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Bill Dilworth
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Users helping fellow users.
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vestprog2@ Please read the PowerPoint FAQ pages.
yahoo. They answer most of our questions.
com www.pptfaq.com
.
> Is it possible to change the font size in a msgbox or input box using VBA
> in
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> Msgbox "All are measured" & Chr$(13) & _
> "service elements.", vbInformation, "Service Elements"