I would like to take the chance of describing the function of "word wheeling" in Outlook Instant Search
The function “Display search results as I type when possible”(word wheeling), can be a little ambiguous.
You may wonder what are the scenarios for which “when possible” applies. The most common is Outlook running in Online mode either
with a primary account or additional mailboxes added without the checkbox
“download shared folders”.
- Display search results as I type when possible This option is selected by default. Clear this checkbox if you don't want the search results to be displayed as you type. For example, you might not want to see any search results until you pres ENTER or click the Search button. The Search button is enabled only if you clear this option. You might also want to clear this check box because the search results are not displayed as fast as you want.
This behavior is intended because in Online Mode the search is performed by Exchange server.
Using Exchange Search, Outlook will send the search string to Exchange Server and the server will reply with the results.
For this reason the user input “hitting enter or the search button ” is required.
Here it is the interesting part, in background when you start a search in Outlook running in Online
I try to search for test1, type test1 and hit Enter or
Outlook will send the search Criteria (test1) to the Exchange server in an RPC package. (more info: http://msdn.microsoft.com/en-us/library/hh354885(v=exchg.80).aspx)
The Server will process the client request (http://msdn.microsoft.com/en-us/library/ee124336(v=exchg.80).aspx) and Outlook will display the results.
Windows Desktop Search role in this configuration is only to enable Instant Search feature.
In online the e-mail are stored only on Exchange Server so Windows Desktop Search (WDS) doesn’t indexes the e-mails.
The functionality is reduced in Online Mode for all Outlook version from Outlook 2003 to the latest Outlook 2013.
Hence, the function Display search results as I type when possible, is not displaying the result while you type.
More information you can consult:
Understanding Exchange Search
Windows Desktop Search