Microsoft JScript runtime error: '__pendingCallbacks[...].async' is null or not an object
Looks like a flagrant Microsoft bug: http://connect.microsoft.com/VisualStudio/feedback/ViewFeedback.aspx?FeedbackID=101974
People have different suggestions
What worked for me is the setTimeout. However, I needed to pass a parameter to the variable, so I used a technique like so:
_gRValue = rValue;
//Do stuff here
} //end of method
To handle the nature of setTimeout, I stored the returned data in a member variable.