Attachment too big
The zipped up database file is 128K which exceeds the 100K maximum for attachments so I'll try to describe it here.
The combo box is in the subform and consists of two columns:
1. dtv_prtcl_id
2. dtv_prtcl_name
When I open the form, "tv station 1" is displayed in the form and tv station 1's dtv_prtcl_id, dtv_prtcl_name (1, protocol 1) are displayed in the subform. I can edit "tv station 1"'s dtv_prtcl_id and dtv_prtcl_name (e.g., update it to 2, protocol 2) using the combo box in the subform. However, I can't associate an additonal dtv_prtcl_id/dtv_prctl_name to tv station 1. When I select an additional dtv_prtcls_id/dtv_prtcl_name (e.g., 2, protocol 2) from the subform list box, nothing happens. The dtv_prtcl_id and dtv_prtcl_name fields in the subform remain blank and the underlying jumper table (tv_stations_dtv_prtcls) is not updated. I hope this make sense!