Which OS?
Which WidgetSet?
Which Lazarus?
This piece of code:
messagedlg('Title','Message',mtInformation,[mbYes,mbNo],0);
for me only gives 3 possible result values:
mrNo if I click "No"
mrYes if I click "Yes"
mrCancel if I press Escape or close the dialog using the X border icon.
This is how it was designed to work, if it does not, then something is wrong.
Bart