It's important to have a copy of the OS unless you are willing to accept that the PC is expendable. But, you might try booting in safe mode and running the system file checker. Certain such files are kept in a hidden folder. From the command line you run "sfc /scannow" (without quotes). If a corrupt or missing system file is detected, XP can attempt to restore it. The noted file is normally part of the System32\dllcache. If it's missing or corrupt, Windows might be able to restore it from there.
I'd be wary of such purchases.I believe a seller who offers such a PC is legally bound to abide by software licensing agreements pertaining to transfer of ownership as contained in the EULA. This would mean any software or documentation that came with the original PC is required to comply with the law...as I understand it. Download a copy of the appropriate EULA and present it to the place you bought the computer from. They should be willing to help.
I have a refurbished computer from a computer store. We recently brought it in to get checked out because it kept restarting. The problem is now that after we were installing some programs (internet,printer, etc) we shut it down but it took too long so we restarted it manualy. When it started up it had a black screen and said "Windows cannot start because System 32/ Drivers/ Ntfs.sys" and then it said that we could use XP disc to fix it. They never gave us that disc and my wo options are one buy a brand new xp disc or two bring it in and have them do it and take a while and charge me. Anyone have any ideas?

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