New (Acronis Disk Director) Partition worked for two days. Other partition on same hard drive seems fine. Error message appeared after intense work on different hard drive preparing for windows 7 dual boot install. (NOT on the drive or partition that is now bad). Suddenly I had a black screen, then a reboot. This invoked Checkdisk, which found some misallocation of files and said it had corrected problem. Next reboot caused checkdisk to run again. This time it found no errors, but my attempt to open the new partition gave error: NTFS Partition not accessible. "the file or directory is corrupted and unreadable" . How can I troubleshoot/access the data? I'm afraid to mess it up further. Stumped. Thanks.