SummaryWhen attempting to run a workflow that was imported from another list, the workflow suspends part way through with the error: "Details: An unhandled exception occurred during the execution of the workflow instance. Exception details: System.ArgumentNullException: Value cannot be null."
SolutionWithin the actions inside of the workflow designer verify that all required fields still contain data. If any required fields are empty, re-enter the appropriate value into the field.
The action with the field in question can often be determined by specifics at the end of the the error message returned from Workflow Manager.