Just so you know, the control is called a tab control. The tabs are where the page name would show if you choose to display it. The area for the subform control that contains the form is known as a page. I make this distinction because Access also has a Tab view for forms and that's a different thing. If you're not hiding the forms all you have to do is set focus to the page. If you want the displayed record on another page to be the current record as well you can apply a filter to the form. Not sure what behaviour you'd get if you eliminate the error, because you don't really want to open the form using that method.
If your pages have subform controls on them, is the source object property (that which dictates which form is in the subform control) being set on the fly, or are the forms not automatically displayed when you switch to a page?
EDIT - You could also have the record id on the main form as well and the subform parent/child property should take care of keeping the related records in view.
The more we hear silence, the more we begin to think about our value in this universe.
Paraphrase of Professor Brian Cox.