Refer MSDN:
These articles contains resources to help developers get up to speed on developing with
Windows Workflow Foundation (WF). There have been significant changes in the model for developing workflows in WF 4 (part of .NET Framework 4) from prior versions of the framework. If you are new to WF we encourage you to develop using WF 4. If you are already developing on previous versions of the framework or you are using WF within Sharepoint we have resources for you as well.
Beginner's Guide to Windows Workflow Foundation[
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Here are some more details which explains:
-Using Workflows with ASP.NET
-Invoking Web Services from a Workflow
-Deploying a Workflow as a Web Service
-Faults and Exceptions in ASP.NET Workflows
-Using Workflows with Web Service Enhancements 3.0
Have a look
Developing ASP.NET Workflow Applications [
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