Symptoms

The following error is seen when packaging a specific workflow using Package and Deployment in the MMC console:

SourceCode.Hosting.Exceptions.SCException: 30003 WorkflowDeploymentService has encountered an error. WorkflowDeploymentService has encountered an error. Value cannot be null.
Parameter name: name
at SourceCode.Hosting.Client.BaseAPI.BaseAPIConnection.RemoteCall(String TypeName, String MethodName, Objectt] Parameters, Booleann] NullList, MarshalMessageType CallType)
at SourceCode.Hosting.Client.BaseAPI.BaseAPI.RemoteCall(String TypeName, String MethodName, Objectt] Parameters, Booleann] NullList, MarshalMessageType CallType)
at SourceCode.Hosting.Client.BaseAPI.BaseAPI.RemoteSessionCall(String TypeName, String MethodName, Objectt] Parameters)
at SourceCode.Deployment.Management.PackageDeploymentManager.RemoteSessionCall(String TypeName, String MethodName, Objectt] Parameters)
at SourceCode.Deployment.Management.ClientSession.OnPackageItems(PackageItemOptions options)
at SourceCode.Management.Controls.AddItemCommandHandler.<>c__DisplayClass14.b__6()
at SourceCode.Management.Controls.Framework.AsyncTaskManagerService.ProcessAsyncQueue()

It is seen when the workflow is selected to be added to a package on the source environment, so it prevents all other items from being packaged once the error is thrown.
 

Diagnoses

This seems to be surfaced by Package and Deployment's validation process when packaging a workflow. This error is thrown due to an item reference that was created from a smartobject that no longer exists in the source environment.
 

Resolution

To remedy the situation, open the workflow in K2 Studio/K2 for Visual Studio, delete the offending item reference and re-deploy the process to the source environment. After that, the workflow can be successfully package.

If help is needed in identifying the offending item reference, a ticket can be logged with K2 Technical Support for assistance.