Microsoft Access Combo Box Search While Typing

If you start typing in a Microsoft Access combo box, it might not search as you type. I eventually figured out the trick to making the search work. The problem occurs when the combo box is based on a query. For the query to work, it must be a DISTINCT query. In other words, if you go to SQL View (select View SQL from the ribbon), and the query is:

SELECT tblCategory.pcCategoryId, tblCategory.strCategory
FROM tblCategory
ORDER BY tblCategory.strCategory;

Change it to:

SELECT DISTINCT tblCategory.pcCategoryId, tblCategory.strCategory
FROM tblCategory
ORDER BY tblCategory.strCategory;

After that the search while typing should work.