EDIT - after doing some research apparently this computer came with a virus installed on it!Returning this computer tower for a refund.  The listing said Amazon Certified Refurbished, but I have a hard time believing that. Now when I click on the link to the product it takes me to a completely different one from a different seller - I purchased from RefurbChoice through Amazon.I've gotten an Amazon Certified Refurbished computer before and have had no issues with it. This one? A complete disappointment. It started great. Booted up just fine, connected to the internet easy, and I was able to start downloading programs and setting it up for my coworker. Then the mouse started to lag. I figured it was the batteries because it had been left on without being used for a while. Nope! System crash - Blue Screen of Death (unexpected_store_exception) then the screen went black and I got a message that said Erased by Killdisk (see photo for details). Powered computer off. When I turned it back on it took me to a boot menu, said IDE device failed, press F1 to boot. I did and it took me to the log in screen, then the desktop, like nothing had happened - except after waiting a minute nothing would respond to being clicked on by the mouse. Then another crash and blue screen (critical_process_died), then to the black screen with the message about being erased by Killdisk. Repeated multiple times.Not sure what they did to this computer but I can't even get it to function long enough to undo everything I've done before I return it.