I was using Vista Operating System and then I tried installing Windows 7, I had two NTFS partition which is the system and the primary partitions. After the Successful installation of Win 7, my primary partition doesn't show.
But it shows in the Disk Management without any drive latter assigned, even it doesn't allow me to assign a Drive latter. I did not try Formatting the partition since my backups are in it.
When you install Windows 7 onto a blank drive, it creates a boot partition of about 100MB which contains the basic boot files and some recovery tools, as well as the "C:" partition which contains the operating system and all the other files.
It's normal for the boot partition to be inaccessible - that's done so that you can't accidentally screw it up.