Do you have the XP disk? If so you can use the recovery console there. You need to go into the BIOS like you did before and set the 1st device to be you optical drive. If you can get to the recovery console one thing that you can do is to type in sfc /scannow. [no period] For this scan windows might need your windows disk so it is best to use that.

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For best results please:
1) State your OS(s), any software involved in your problem, & any major updates (i.e. service pack, version, edition, service release, roll up, beta release, distribution [Linux], etc.) to your OS/software as applicable to your problem.
2) For hardware issues also provide your system information: RAM, processor, etc. in addition to your OS.
3) If you have more than one OS on your computer, how does your problem relate to your other OS(s)? This is especially important for hardware issues.
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If you don't know your system information please consider running our hardware scan and post or PM me your link.