fanman,
I tried opening the shipping example Read TDM File.vi and turned various sections of the code into a subVI to see how LabVIEW handled the reference and it just created normal indicators in the subVIs and bound them to the connector pane. Without knowing more about your VI I'm not sure what may be going on -- it would be helpful when you post to include the version of LabVIEW you are using, the actual text of the error, and a simple VI that recreates the error you are seeing.
Doug M
Applications Engineer
National Instruments
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