HELP! Add item to multi-select listbox from text box in form

[Bevos]

Hello, I have several multi-select list boxes on a form which have a choice of 'other (specify)' and the user then enters the non-present information into a nearby text box (Listbox_Other). I would like to add the entry from Listbox_Other to the multiselect listbox choices (these are populated by a separate single column table). I made an example to make this a little clearer and have attached a copy here. In the example there is a list of encyclopedias with the option 'other' and if the user selects that option they are directed to the 'other choice' text box. Could anyone help me with the next step of getting the information from that text box into the listbox?

Thanks so much!
Bevo S.

 

[DCrake]

You cannot add items to a listbox that rowsource type is not Value List. You would have to append the item to the table then requery the rowsource.