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The Category Codes grid displays existing categories. You can search for existing categories by clicking in the filter row in the grid columns and entering in the desired information. By default, the grid sorts numerically and then alphabetically. Click on 
to generate a quick extract (CSV or EXCEL format) based on what you filtered. Click Click on any row of the search results to see a highlight view of the record. Click the view icon 
to view a particular category. From there, you have the option to edit it.
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To mass update category codes on existing items, please refer to the System>Import System>Import chapter for more information. The The import process will allow you to update all items in the CSV file to a new category code. The primary purpose of this is to allow you to change item categories that may have been assigned by an appraisal company to a more meaningful code for your district.