the BIOS is not set to read the CD/DVD drive first?
The BIOS has an 'order' in which is listed what drives to attempt to read first. Often this 'should' be the optical drive, (CD/DVD drive), and if it finds no disk there it then goes onto find the hard drive. But sometimes the BIOS is set to read direct from the hard drive first. In which case it will never see the disk in the optical drive during boot up.
If that is the case here you will have to enter the BIOS to change the order of the bootup so that the CD/DVD drive is listed first.
If the BIOS is already set to do that, (and it should be on modern systems), then either the optical drive has failed, or that "Boot Disk" is not a boot disk, or the boot disk has failed.
CD/DVD disks do fail and when that happens we can try to 'copy' the disk to another and try again. That sometimes works.
If the optical drive has failed then you need to replace it.
If the boot disk is not a boot disk, then the BIOS will not boot from it, but that should give an error message similar to, "Please insert system disk".
As to Vista, at what stage does it fail to load? Can you access Vista's "Safe Mode" options?
Mark
Windows Vista had updates, so I let it update. My system crashed and won't boot. I put the factory boot disk in to system restore, but the disk drive won't read the disk. Help?

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