After you try to complete a full format of a hard disk or a removable media in Windows Vista, the full format is not completed. When you try to access the hard disk or the removable media, neither can be accessed. The hard disk or the removable media is a RAW volume.
Note A RAW volume is a volume that has never been formatted and does not contain a file system. Examples of file systems are FAT, FAT32, and NTFS. Typically, programs that do not require a file system write to a RAW volume. These programs perform direct I/O operations to the RAW volume.
This issue may occur if the full format process cannot complete correctly. For example, this issue may occur if the cluster size that is specified for the full format is too large to format the disk.
To work around this issue, click Restore device defaults when you format the hard disk or the removable media.
When a full format is completed in Windows Vista, any data that previously existed on the hard disk or the removable media is overwritten with zeros. If the full format cannot be completed after the disk has been overwritten with zeros, the disk appears to be a RAW volume.