When an association between one or more customers and an item no longer applies, you can change the associations.
From the List tab of the Item Master (SP) application, select the item that you that you want to change customer associations for.
On the Item tab, click Show/Manage Customers next to the Customer field.
In the Add/Modify Customer Associations window, change customer associations:
To add a customer association, click Select Customers, select one or more customers from the list, and click OK.
To remove a customer association, click Mark Row for Delete .
Click OK to save your changes and return to the Item tab.
Associate customers with an item