Batch requests
You can also execute batch requests to a web service.
To enable batch requests, perform the following:
    - Open your 
web.config file. 
    - Inside section 
<appSettings>, add
    <add key="aspnet:UseTaskFriendlySynchronizationContext" value="true" /> 
    - Save and close the 
web.config. 
For more information about batch requests, see oData docmentaion » Batch Requests.