can't build a link between forms

[Alex]

I've put comboBox with Raw Source from the table with
Category field (Category Code is primary key) on my main
Form.

I've created a subform based on a query with Category
field and put this subform on the main form.

When I'm trying to set up Link Child and Master Fields
I'm getting the following message:
"Can't build a link between unbound forms."

Could anybody clarify how I could resolve it?

Thanks

 

[PC Datesheet]

Alex,

The first requirement for a form/subform is that the fields you want to assign
to LinkMaster and LinkChild must have a relationship. Even if they have a
relationship, the form wizard can only automatically assign the LinkMaster and
LinkChild properties if the form and subform are bound to tables or queries, ie,
the record source of each must be assigned. If either or both are unbound you
will get the message you are getting. If the fields are related, you can enter
the LinkMaster and LinkChild properties.