Windows Vista user interface guidelines
Developing software for Windows Vista
http://msdn.microsoft.com/windowsvista/experience/The preliminary Windows Vista user interface guide is out! Microsoft is trying to encourage developers to create more consistent UIs. Here are some of the highlights:
#1: Use the new system font "Segoe"

#2 Use the built in controls instead of designing your own:

Editorial: If you really want to have your own client area look, check out DirectSkin.
#3 Don't try to mess with the non-client area (the frame of the window).

And try to support the base resolution of Vista -- 800x600 in your apps
Editorial: Again, if your app needs to have its own unique frames, use DirectSkin.
#4 Use icons that are consistent with the new Windows Vista style:

Windows Vista icons go from 16x16 to 256x256. So make sure your icons look decent in those resolutions. PNG is the new icon format.
Editorial: One of the best places to get PNG images is the ObjectDock gallery on WinCustomize.com
#5 Use the new dialog APIs to create dialogs that are easier to understand:

#6 Use the Aero Wizards instead of Wizards '97. Specifically, don't have the first page of a wizard be a welcome, have it be functional from the start. Avoid congratulation pages.
#7 Use Explorer style interfaces with a back button.

Have your UI try to be consistent with what people see the most on Windows and that's the Windows Vista Explorer interface.
#8 Use the new Windows Vista search

This means supporting the new "Find as you type" feature and don't use labels but rather put "Type to search" in the edit field.
#9 Use the Windows Vista tone in all UI text. That means make your text clear, natural and concise. Use every day words.
#10 Keep your UI clean!
That means keep your commands task oriented and in a hierarchy. Make sure commands are accessible from the keyboard. Put effort into having only the most commonly used commands be top level (visible) with infrequent commands put at a lower level. A good UI shouldn't display every possible feature command at once.
# 11 Use the notification feature of the system tray sparingly.
#12 Save time for the fit and finish. Don't look at making your program polished as a minor detail. Make it a priority.
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