Could you drop a writeln in to print the value of "str" before you place it in the Combo Box?

Also, when you say you get a blank value - do you mean that the combo box list is blank, or that the "selected value" of the combo box is blank?

Also, is ParentName in the main form? Subform? Table View Subform?

Also, is CMS.db the same .db as is code? If so, why not use @fn? If not, maybe use the full path - just to avoid confusion.

You mention that this code is in a subform and that you want to reference ParentName from the main form - yet there is no code included to illustrate that. So when you say, ParentName is blank - is that something you are seeing on the form, or is there other code elsewhere trying to access it from the main form?