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SystemDefinition: NullReferenceException when creating an Alias



I'm programatically creating a SystemDefinition and I have the problem that I cannot create an Instance of the "Alias" class when using the (String, String, String) overload. No matter what texts I pass as arguments, I always get a NullReferenceException saying "Object reference not set to an instance of an object". 


What's wrong?





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To get an efficient help, I suggest you to identify your VeriStand and other tools versions and maybe to post an extract of your code


Bes regards,

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My VeriStand Version is 2012 and I'm using IronPython to create the system definition.


Example code:

Alias('Alias1', '', 'Targets/Controller/Hardware/Chassis/DAQ/PXI1Slot5/Digital Output/port0/NIP0_36')


I don't think this has anything to do with IronPython since I get the same error when using LabView.


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basically LabVIEW and other text based programming languages are always referencing to the .NET API of VeriStand.

Please check the following link, they create an Alias for a custom device


create an alias from a custom devic page - Discussion Forums


Here is also another example basedLabVIEW Walkthrough: Modifying Models in a System Definition File on LabVIEW


Are you able to create the Alias in LabVIEW? If so, please use the same .NET calls in Iron Python


Kind regards,




NIG, Munich


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Hello RupiDo,


when I opened this thread I was already convinced that this is just another Bug in VeriStand. I just wanted you guys to confirm it. In your second link Jarrod S. confirmed that it is a bug (I didn't find that answer although I searched the forum before posting).


Why isn't this bug listed in the known issues list for VeriStand 2012? I have wasted so many hours trying to fix things that in the end turn out to be known bugs in VeriStand. Frustrating.


I was able to workaround the bug using the FindNodeByPath method.






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Hi Krid,


I just double checked the known Issues in VS 2012. I agree it's a hassle that the creating Alias instance bug isn't listed. Pardon, for this fact.

Generally I will forward the concerns about documentation to the internal group, who are in charge of the docu.


Thanks for your patience.


Kind regards,



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