can you tell us the manufacturer brand and model number? Most manufacturer's put a recovery partition with an image of the drive that can be accessed during boot for the purpose of recovery.
Of course if the system is a home built from components or a commercial model that the seller re-partitioned and formatted that won't help.in this case you need to contact the seller and have him send you the installation DVD or purchase one for yourself. That seller is your support.
I bought a computer on craigslist a while back and it's been working great and all but lately it started slowing down really badly. I play WoW and Skyrim mostly. I used to be able to play at 60 fps or so now I can drop from 30-15 fps. I considered doing a system restore but there weren't any restore points because there weren't any being created every week or so for some reason. So really the only option I have now is to completely restore my computer to it's original settings. When I first bought the computer the guy who sold it to me told me that he'd wiped the hard drives clean and that's what I'm trying to do right now but he never gave me a back up disk or a disk for the OS which is what I'm really worried about. He had windows 7 ultimate installed. I'm afraid that if I try to do a factory reset that I won't have an OS to reinstall onto my computer.

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