Radiobutton / Checkbox stays checked while changing state

I'm building a WPF-application with Expression Blend 4 and I've got a problem.

When I check a radiobutton or checkbox and I want to Log Out (a state that hides all the checkboxes and slides i开发者_JS百科n another screen) and I log in again I still see the radiobutton checked.

Is there a way to terminate all 'checked-state' when I press a normal button to go to another state?

Thx a lot!

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It might be that I don't fully understand your question, but shouldn't you address this directly from code-behind in an event related to your logging-out?