Can I create CRM workflows using .NET 4?

Question

I would like to take advantage of .NET4 for Dynamics CRM4.0. It is great for most things but I get a file not found exception when trying to register a workflow. It can't find System.Workflow.ComponentModel 4.0.0.0.

Is there a workaround?

Answer 1

CRM 4 is built under .NET 2.0/3.0. So, the only way to work with .NET 4.0 and CRM 4.0 is to isolate them in their own process. CRM 5.0 will use .NET 4.0, so you will be able to use it with the next version of CRM.

With some tweeks you should be able to make it work partially with .NET 4.0, but if it like CRM 3.0 and .NET 2.0, other parts will break without workaround.

More info can be found on the Ascentium blog at http://xrm.ascentium.com/blog/crm/Post834.aspx