1. Navigate to Lists > Mass Update > Mass Updates.
2. Click General Updates.
3. Click Vendor.
4. Enter Criteria. (Results should include at least one vendor with Category = Tax agency)
5. Click Results tab.
6. Add Category field under Field column.
7. Click Preview.
8. Click Perform Update button.
Result: Error: You cannot change the vendor category if the vendor is a tax agency.
1. Enter Criteria: Category is not Tax agency.
2. Perform Update.
3. Manually edit the tax agency vendors by opening each record in Edit mode.