It is a whole lot of less hassle to do a clean install of Windows 10/11 then it is to send the computer back. Takes 10 minutes tops on most computers and you don't have to box the computer up, print out a return label, and take the box to a shipping store. Plus, as I stated, only a fool would not do their own clean install of Windows anyway on a used computer purchased over ebay, or a pawn shop, or a thrift store, or craigslist, or facebook unless they personally knew or trusted the seller. But that's just me.