An Error Has Occured

System.ArgumentNullException: Value cannot be null. Parameter name: input at System.Guid.Parse(String input) at IBSCustom.CombinedWorkflow.MVCWidgets.InventoryWidgets.InventoryDetailsDirectorController.Index() in E:\iBeanz\Alteso\BitBucket\IBS.V.2\IBSCustom.CombinedWorkflow\MVCWidgets\InventoryWidgets\InventoryDetailsDirectorController.cs:line 32