ARCHIVED: How do I assign or mass update tax codes to Customers and Vendors?

Go to Setup, Settings, Company, Sales Taxes, and Tax Codes. Click the Assign Tax Codes... button.
Under the Show radio button, select either Customers or Vendors.
Select the With this Default Tax Code: dropdown box to show what default tax codes are assigned to your customers or vendors.
Select the multiple Customers or Vendors on the list by clicking Select All or holding down the CTRL key and manually selecting each record.
Under the New Default Tax Code: dropdown, select the new tax code required and click Assign.