Dependent combo boxes

[elanus2]

I am trying to design a form with three dependent combo boxes, where selections in the first determine those displayed in the second, and so on.

I copied a functioning example (Country, State, Town), but when I use new tables of my own, the combo boxes do not allow selection, even though the correct data is displayed in the drop-down boxes.

The properties of the fields on the form are essentially unchanged. The main difference between the two is that there is a fourth table in the working example which has the identification codes of the three related records, and that record is the source for the form.

In my modified database (Family, Genus, Species), I have created a query for the details of the linked tables, and I am trying to use that as the source for the form, rather than a record with the codes of related records.

Why am I unable to select from the drop-down box?

 

[elanus2]

In case anyone has a similar problem, I have discovered the reason. It was to do with bound and unbound controls.

The original form had controls bound to the identifiers in the fourth record. When I amended these to my query, I bound them to autonumber identifiers, hence the refusal of the form to allow me to select them (and hence change them).

Since I am not looking to update the source records, just use them for drop-down values, I unbound the controls and it all works beautifully now.