Finding Duplicate Values in a Data List

When you maintain organizational records in an Excel data list, you must be careful not to enter an order, customer, or supplier into your list more than once. As an example, suppose that you own a business and accidentally created two customer information records for the same customer. If you generate a mass mailing, that customer would receive two copies of your mailer, costing you money. What’s worse, if you and your employees don’t realize the customer is in your list twice, and each entry has its own CustomerID value (like the customer number you see on catalogs mailed to your home or business), you could end up assigning some sales to one ID and some to the other. Should the customer call to ask ...

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