You can search by the product's UPC number or by the data specified in the User Defined #1, User Defined #2, User Defined #3, or User Defined #4 field on the Price Updating ID Maintenance window in Product Maintenance.
For example, Instead of using UPC numbers to identify its products, a vendor might use its own part numbers. One of those fields would contain that user-defined part number. Point to that field by selecting User Defined #1, User Defined #2, User Defined #3, or User Defined #4. If you point to one of those fields and it does not contain any data, the update will not work because there is nothing to match.
Note: For the bulk of your products, an entry in any of these fields will typically have been loaded during the initial Eclipse data conversion, through Mass Load/Update, or by creating products using a vendor supplied diskette and this program.