G’day all, just a little snippet of news to share – remember .Net 4 Platform Update 1? The update with State Machine? Well, we are almost up to Platform Update 3 now, and the beta version is available for download.

Note that this is not the final PU3, this is just a beta version of PU3 - it may break things or screw up your machine somehow, so treat it with a little caution. That said I can think of two reasons you might want to try the beta version despite the risk.

1 - to Beta Test!

If any of that bad stuff does happen you can let MS know about it via the usual channels, and make it less likely to be an issue in the final PU3 (and all the future framework versions which have to be backwards compatible with PU3).

2 - for the updates!

There are bug fixes and a couple new features to enjoy – see the full KB article: http://support.microsoft.com/kb/2599651 but here are the WF4 related highlights:

- “Support running Workflows in partial trust”

and..

- “Enable WF messaging activities across multiple hosts”

This one is kind of exciting. Have you ever tried to use Receive activity outside of a WorkflowServiceHost? Well, basically it was impossible. But PU3 introduces new types which can be used to provide support for Receive activity in your own host. The key puzzle piece is a type called SendReceiveExtension, it is one of those host extensions consumed from Receive/Send activities Execute() method via activityExecutionContext.GetExtension<T>(). I can find no documentation for this type yet, and I don’t know much about it myself yet, but hopefully this crumb will let sufficiently motivated individuals figure it out.