|Outlook Developer Reference|
expression A variable that represents a Search object.
A search can be synchronous or asynchronous. If the search is synchronous, code execution will pause until the search has completed. Conversely, if the search is asynchronous, code execution will continue even though the search has not completed. In this case, use the Search object's Stop method to halt the search. In order to get meaningful results from an asynchronous search, use the AdvancedSearchComplete event to notify you when the search has finished.