I guess it depends on the design and the options available.
If you've got a db as part of your project you can use it to store the options (or select what values had been previously saved it a field with a select distinct).
If you don't have a db, you can use a list in My.settings and use that to save the possible options or a flat file or an XML file or whatever you are comfortable with.
Share more info, perhaps the code that you use to populate the combobox and possibly how you want this to work out.
(0) here specifies the idex of your control. in specifying your database and table do not use single quote instead, use the symbol on your keyboard leftside of 1&! key but not this (~). I hope it helps.