UI automation cannot find an element. Inspect Object can.

Hi,

I'm attempting to grab a particular control using UI automation.  The Inspect Object tools shows the control in the appropriate tree, and I can even navigate to it and have it be highlighted, but my code can't see it.  Here's the code (where 'root' is the parent of the control):

Condition elementPropCondition = newPropertyCondition(AutomationElement.AutomationIdProperty, id, PropertyConditionFlags

.IgnoreCase);

AutomationElement theElement = root.FindFirst((TreeScope.Element | TreeScope.Descendants), elementPropCondition);

Any ideas?