I bought this with the intent of installing it on my old computer, my computer couldn't take it however (very low memory and too small a hard drive, had to uninstall it) and now I am stuck with this software and it is useless to me since my new computer already came with it pre-installed. This OS is Microsoft WindowsXP Home Edition with Service Pack 2 (Upgrade Edition. Use only if you already have a previous version of Windows 98 or above installed and want to update it. Do not buy if trying to update Windows 95, you need the Full Edition for that.) Comes in original box with all manuals, brand new condition. It was very recently bought on 9/7/05 from Staples. Please see my Amazon Zshop profile, I am a reliable seller.