With respect to Windows XP, Microsoft Vista changed the default font size from 8 to 9 and changed the size of the window borders (among may other changes). As a result, programs written using Delphi 5 (and others) will not run. To be more specific,

• Components pinned to the right and bottom borders will not be displayed
• Because the text is automatically enlarged, the form size is larger than the rendered size and must be scrolled or enlarged to use it

Property	Type	Default	Description
AllowVistaScaling	boolean	false	Vista automatically changes the font size if a default font is used. true - Allows Vista to use larger fonts false - The form will be the same size in both XP and Vista
AutoScroll	boolean	see note	At design time, this component forces form.AutoScroll to false and saves the original value here. At run time, this value is used to control form.AutoScroll after the program has rendered. Manually edit this at design time to control the automatic display of scroll bars when the form is manually resized at run time. When form.AutoScroll is true at design time, the form's Height and Width properties are saved in the *.dfm file. In order to have a form render the correct size in Vista, the ClientHeight and ClientWidth properties must be used. These are saved in the *.dfm file only when form.AutoScroll is false.