In such cases you first boot into the BIOS to set the laptop to boot from the optical drive, Then boot from the recovery disc (it seems old enough to have come with such a disc) and try to restore it to factory conditions.
In between you might prefer to boot from some Linux disc and have a look at the hard disk.
If you don't have a recovery disc, choose between buying a supported version of Windows to install yourself, or installing free Linux.
I just recently had the LCD replaced to my old Sony VAIO. The computer model itself is in great condition, however I haven't used it in about 6 years. The repair shop I took it to fixed the screen but when the computer turns on it shows the VAIO logo then goes black and restarts again. The guy said it could be either the battery or the hard drive. Is there a way I can boot it up and stop the loop? I took the battery out and left it on but plugged in to see if it changes but its on the same loop. Any help is appreciated!! Thanks

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