Classic: Approving Bidders from Past Sales
Make sure you have selected the "Bidders" tab within the auction itself.
Once you have are in the "Bidders" tab, go to the classic bidder approval page:
When you are in the Classic Bidder Page, please click the dropdown menu on the right hand side of the Classic Bidder Page, and select the sale which you want to copy approved bidders from past sales.
Finally, after you choose the sale from the dropdown menu, the tab to copy approved bidders from past sales will load.