app.config should be just what it says...application config stuff.

You could save user specific data in isolated storage.

>According to this guy http://ryanfarley.com/blog/archive/2004/07/13/879.aspx it's not a good idea to write to App.Config:
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>Warning: As a rule of thumb, it is not good to write back to the config file. The framework does not include this ability for a reason. If you want your application's users to not require administrative rights then it is always a better idea to store settings in the user's documents & settings directory or in the registry if needed. That said, this won't break anything and does come in handy for utility applications etc.
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>1. Why not? Isn't the point of App.config to save app settings?
>2. If not, then where's the best place to save user settings?
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>Thanks