Subform is not opened error

[aprentice]

I have a subform inside a Form.
When I'm trying to upadate the subfrom from an event triggered by a control in Form I get the error message that subform is not opened.Why is that?
I've tried commands MoveTo or Select (subform) before update command in order to force update command to understand that subform is opened but without any result.
I guess is a common problem but I can't find the solution.

 

[RuralGuy]

When a form is used as a SubForm, the form is not open. You must reference the SubForm through the MainForm. Here's a good link to put in your bookmark collection.