I need some help. looking at the Screen shot. The Inventory Category, Sub-Category and Product are all Conditional drop downs. The table that is suppose to populate the model vendor and the rest has been deleted i think the previous Admin. How do I fix the problem.
Start by right clicking into Model, Vendor, etc and look at its properties. Do they show that they're lookup fields from a related parent table? If so, the properties page will provide a link to the relation so you can see where it comes from. The lookup fields have '+' signs next to them that when clicked show you the associated parent element. If that is blank, the source or parent field has been deleted.