On my desktop PC running 64-bit Windows 7, I have one hard drive with two equally sized partitions C: and D:; and a second hard drive with one partition J: Windows Explorer shows all 3 partitions correctly: http://i50.tinypic.com/2nqts2q.jpg And so does Computer Management: http://i45.tinypic.com/2n9glxz.jpg And I've been reading and writing files to D: with no trouble. BUT: HDM 12 does not recognize partition D: Under backing up disks and partitions, HDM 12 shows it as an UNNAMED and UNALLOCATED partition (not as D) http://i48.tinypic.com/s3hbn8.jpg Furthermore, HDM 12 thinks that the file system in D: is invalid, even though Windows Explorer has no trouble reading and writing files to it (see above). http://i45.tinypic.com/2mfzt77.jpg And under "Which files and folders to back up," it doesn't show D: and its files and folders at all: http://i46.tinypic.com/261ksnr.jpg What's going on here? Could either of these be the cause: 1. The "Smart Backup Wizard" found about four I/O errors, which I told it to ignore. 2. Prior to running HDM 12, I had run chkdsk on D: to check for errors, as follows: I selected D:, right-clicked on "Properties", then selected "Tools" to run error-checking on D: It told me I needed to dismount the drive temporarily, so I did. But I rebooted, and as you can see, D: is fine as far as Windows is concerned--but HDM 12 still can't see it. Any ideas? I need to back up D: My hard drive is failing so I need to replace it and rebuild C: and D: on the new drive.