In windows 8 store App, if a combobox is included inside a popup like a normal fly out, and the selection changed event cause the pop up to close, and the App runing on ATOM processor machine then the App will crash most of the times. this issue just happens on ATOM processors. The Reason: Since there’s a ComboBox inside a Popup, when the ComboBox’s SelectionChanged event fires, the outer popup gets closed. If garbage collection (GC) happens to come in at exactly that point, it exposes a ref count problem. (The GC causes the VisualState to go away, but the ComboBox is still on the call stack and wants to use it.) Temporary fix: Try to change your app logic to avoid closing the pop up at the time of selection changed event fired. This issue was reported to Microsoft and a request for fix has been submitted and they did a hot fix which solved this issue.
Maheshkumar S Tiwari edited Original. Comment: Added Tag and minor edit