I spoke to several sellers who claimed they had no idea. One of the problems with Craigslist, eBay, and Facebook sellers is they often won't specify the year of the machine you're buying. Apparently, Gmail also checks the OS version. Even when using other browsers, Gmail wouldn't work. I got hit with Chrome not upgrading on a too-old machine. I reached out to OWC, which sells refurbs, and it told me a lot of folks are running somewhat older OS versions. See: Which Mac to buy? 10 tips to help you decide If you see inaccuracies in our content, please report the mistake via this form. If we have made an error or published misleading information, we will correct or clarify the article. Our editors thoroughly review and fact-check every article to ensure that our content meets the highest standards. Our goal is to deliver the most accurate information and the most knowledgeable advice possible in order to help you make smarter buying decisions on tech gear and a wide array of products and services.

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Refurbished 2015 macbook pro 13