Exactly. I want to make a listbox item NOT selectable and in some conditions make it selectable again. I know it can be done in Foxpro by leading your item value with an '\'. But seems it doesn't works the same for Access...
I don't think the simplicity of what your looking for is possible.
You could work something out through code, that deselected an item that was selected if it is not supposed to be selectable and trigger it in a listbox_Click() event, but I'm pretty sure that is not going to give you the desired effect your looking for.
Usually I just continually update the listbox only with items that are appropriate for the current condition.
Sorry , I'm not of more help.