LabVIEW's .NET Constructor Nodes will continue to point to your original assembly. To have the Constructor Node point to the new assembly, we need to make sure that the .NET Runtime is not seeing the old assembly.
To load a new version of an existing .NET assembly:
- Close your Project (or quit LabVIEW if you aren't using a project) that contains the VI you were using to load the .NET assembly
- Move the original .dll so that the .NET Runtime is not able to find it
- Create a new VI; place a Constructor Node and point it to the updated .dll
- Close this new VI without saving
- Open your original VI and point it to the new .dll