"Unknown variable or property name" error

[domcorrado]

Hello, im using teststand 2021 sp1 and the problem is the following: im using a custom steptype with some controls and im trying to write a pre-expression to assign a value to one of this controls.

It is a numeric and the name is Step.Parameters.Device_Select. Whenever i try to use this and this control only (there are many others but no problem with those) i get the following warning: Unknown variable or property name "Step.Parameters.Device Select"; If you are certain that the expression will evaluate correctly at run time, you may ignore the error or use th #NoValidation directive to suppress the error.

I double and triple checked the spelling and the labview code of the steptype in question and everything is correct. Anyone got any idea why this happens? and how can i fix it? 

thank you

[Oli_Wachno]

Here is a typo 😉

[domcorrado]

yeah i meant to write Device_Select. In teststand its written correctly tho

[Oli_Wachno]

Please clarify:

you are talking referring to a pre-expression (which refers to TestStand) yet your error seems to show in conjunction with LV. Is it that your custom step type actually uses that VI as a PreStep. 

Can you provide screenshots of the type definition and the actual code?

This would really help helping you