Reboot without an installation CD

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I can't log into Windows (XP Professional) It goes to a black screen, that
says:

"We apologize for the inconvenience, but Windows did not start successfuly.
A recent hardware or software change might have caused this.

If your computer stopped responding, restarted unexpectedly, or was
automatically shut down to protect your files and folders, choose Last Known
Good Configuration to revert to the most recent settings tht worked.

If a previous startup attempt was interrupted due to a power failure or
becasue the power or Reset button was pressed, or if you aren't sure what
caused the problem choose Start Windows Normally.

Safe Mode
Safe mode with networking
Safe mode with command prompt

Last known good configuration (your most recent settings that worked)

Start Windows Normaly

Use the up and down arrow keys to move the highlight to your choice.
Seconds until windows starts: 30"

I have tried each of these options , None of them work.

I DO NOT have the windows XP disk for this computer

I can't replace any files or fix any files if I can't get into anything.

Please help!!!

Thank you so much for you time it is GREATLY appreciated

Stephen Ross