You can check for duplicate customers or accounts when you import accounting data into Customer Manager. That way, you avoid keeping two copies of the same records and splitting essential information between the copies.
On the Customer Manager Tools menu, click Check for duplicates.
Duplicate records will appear in the Resolve Duplicate Records dialog box. Records preceded by a "#" might have been imported from an accounting program or a customer list.
Select one of the following:
Keep the selected record and delete the unselected records You can choose to link all communication items, opportunities, and invoices to the selected record. Or, you can delete the items when you delete the unselected records.
Keep all records You can choose to ignore the conflicts and keep all records.