C# provides us with the IS operator

–returns true if an object isan instance of a type

AS operator attempts to cast an object to a specified type

–returning the instance cast to the type
–null if not possible
–does not raise an exception

COM object that has been separated from its underlying RCW cannot be used

COM object that has been separated from its underlying RCW cannot be used. Error occured when i closed the application in C#.net

How to fix it?

 I am using event watcher in my Application . So I didn't stop when i close the Application ,So I Stop eventWatcher. solved issue