Someone emailed me a question about whether or not you can specify credentials when
using the OOB SendActivity in WF 3.5 because they heard that you had to write a custom
activity to accomplish this.  You do not have to write a custom activity. 
While it is true that the SendActivity links to a named endpoint, and if you use the
configuration file to configure your endpoint you can’t specify specific credentials
(a username and password for example),  WF 3.5 has a OOB WorkflowRuntime Service
named the ChannelManagerService.  The ChannelManagerService (which I described
in my article on MSDN – here http://msdn.microsoft.com/en-us/library/cc626077.aspx
allows you to pre-populate some or all of the endpoints you want the SendActivities
running inside of your WorkflowRuntime to use.  So you definitely can programmatically
configure an Endpoint that the SendActivity can use without having to write a custom
activity.



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