CrystalDiskInfo is reporting a Current Pending Sector Count of 24 on my 1 TB Toshiba HDWD110 hard drive. The Uncorrectable Sector Count (C6) changed from 4 to 16 and then back to 0, while the Current Pending Sector Count (C5) went from 0 to 16 and is now at 24. Is the drive failing, and can it still be safely used as a secondary drive after reformatting?
3 Answers
Back up anything important immediately and plan to replace the drive. A rising pending-sector count means the drive has encountered sectors it can’t reliably read, and the changing uncorrectable count is also a warning sign. Even if a reformat temporarily clears the values, it wouldn’t make the drive trustworthy for important data.
A temporary drop in the uncorrectable count doesn’t necessarily mean the drive recovered. SMART values can change when sectors are retested or remapped, while the growing pending count still indicates instability. Copy your data off it first, then replace it rather than trusting it with anything important.
The values may have been mixed up in the description—pending sectors are usually listed as C5, while uncorrectable sectors are C6. Either way, both attributes are concerning, especially since C5 is increasing. The full SMART report would provide more context, but I wouldn’t rely on this drive.
So it shouldn’t be considered safe even as an extra drive after reformatting? I’m going to arrange a replacement soon.