Ok ..To fix this issue, you will have to repair your Windows Vista OS using your Vista bootable system disc, so as not to lose any of your programs/data. To do this, please follow the enlisted:
1) Restart your computer and go to your system's BIOS Setup menu by pressing F2 at your bootup screen, and check in the boot order if CD/DVD drive is set as the first boot device, before Hard Drive. If not, please make changes accordingly and save and exit.
2) Now insert the bootable system disc in your computer and when press any key to load from the disc when prompted to do so.
3) Press ENTER when you see the message To setup Windows Vista now, and then press ENTER displayed on the Welcome to Setup screen(Do not choose the option to press R to use the Recovery Console).
4) In the Windows Vista Licensing Agreement, press F8 to agree to the license agreement.
5) Make sure that your current installation of Windows OS is selected in the box, and then press R to repair the same.
6) Now, follow the instructions on the screen to complete Setup.
7) Reboot your system and load up your Vista OS as you do normally(dont boot from the disc again), and follow the steps given to repair your OS, your data wont be lost, your system settings will just be repaired and reverted back to default settings.
Hope it helps ..keep me posted.
Regards
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