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The only thing I can think of is whether you are deleting the small about 200 mb EFI partition on the drive. This small partition is needed to boot off the hard drive. You should see a separate large partition occupying the rest of the drive, which is the one that you need to install Windows into it. If you partition the entire drive, you loose the special hidden EFI partition and will not be able to boot form that drive. If this is not the problem, there may some low level format corruption on the drive below what Bootcamp accesses; you may want to try the whole process on a fresh drive.
The only thing I can think of is whether you are deleting the small about 200 mb EFI partition on the drive. This small partition is needed to boot off the hard drive. You should see a separate large partition occupying the rest of the drive, which is the one that you need to install Windows into it. If you partition the entire drive, you loose the special hidden EFI partition and will not be able to boot form that drive. If this is not the problem, there may some low level format corruption on the drive below what Bootcamp accesses; you may want to try the whole process on a fresh drive.