Excel's VALUE function has only one argument: where a is the value stored as text that you want to convert into a number.

If you've used data validation in Excel before, you probably selected the relevant cells, clicked "Data Validation" in the Data tab on the ribbon, and created the rule in the Data Validation dialog ...

Product IDs, serial numbers and other reference numbers require a unique identifier to avoid confusion when referencing a product or specific data point. Although you can manually enter unique numbers ...