Hello everyone, not sure there is a connection but before I describe the problem it should be noted that I went into Disk Management and started formatting the drive (WD30EFRX) and after a short time I clicked Action -> Refresh which caused the formatting to stop and the drive disappeared. I do not know if this is the reason but from that moment this is what happens: after a restart to the computer the drive is displayed and working. Fast formatting works. Performing full formatting causes the drive to disappear. Copying files (at least a few GB) causes the drive to disappear. When the drive disappears then I actually hear the speed of the disk slowing down or maybe even stopping, after a restart the drive reappears and the same story. I performed chkdsk, did not resolve the issue. Would appreciate help. Thanks.