I have three large hard disks that I backup my system to in a round-robin fashion, a different disk each day. Yesterday, I was checking the disks for errors using chkdsk and smartctl. The computer is laid out on a work table: mobo, PSU, and 7 hard disks, all blown upon by a very large fan. For lack of room, one hard disk was on top of another, and when I lifted off the top one to read the S/N of the one underneath, I heard the three tones twice as the upper disk went offline and then back on. Apparently either the power or the data connector is intermittent. Now, Disk Manager says "Disk 4, Basic, 931.51 GB, Online, unallocated." The hard disk (Q:) no longer appears in File Explorer. EaseUS Partition Manager says Disk 4 has a MBR, but no directories, also 931.51 GB, and nothing else. File system is NTFS, and NTFS keeps a duplicate MFT. Does anyone have any suggestions on how I can recover the file system on this disk?