A healthy drive copies a file or fails randomly. A drive with pending sectors fails the same file at the same percent, every single time — because one small damaged patch of surface holds a piece of that file hostage.
Of all hidden drive faults, this one has the clearest fingerprint. You copy a folder and everything flies — except one file that crawls, freezes at a fixed percentage, and eventually errors out. Copy it again and it dies at the same place. Meanwhile the health tool still smiles: these damaged spots have a special status called pending, and pending damage is easy for headline percentages to shrug off. The video lists failed and corrupted copies among the first signs of a hidden problem; this page explains the mechanism precisely, shows you how to confirm it in one SMART row, and lays out the honest options — including the uncomfortable truth about the data already sitting in the damaged spot.
A sector is the smallest patch of disk surface the drive reads and writes. When the drive tries to read one and the data fails its error checks, the firmware does not immediately declare it dead — it marks the sector pending and keeps retrying, because a later attempt might succeed. The sector stays in this limbo until something writes to that exact spot, which forces a final test: if the write works, the sector returns to service; if not, it is retired and replaced by a spare (which is when the reallocated count rises). Pending sectors are therefore undecided damage — and while they are undecided, every read of that spot costs seconds of retries. That is the freeze inside your file copy.
Open CrystalDiskInfo and read C5 Current Pending Sector Count, Raw Values. Zero is the only healthy number. Anything above zero confirms pending damage exists right now, whatever the health headline says. Then run the simplest field test: copy the suspect file on its own, twice. A file-system problem moves around; a pending sector does not — the copy stalls at the same percentage both times, because the same physical patch is being retried. Also run chkdsk C: /scan (use your drive's letter) to learn the file-system side of the story: it reports whether Windows' own records have been hurt, which matters for what can be salvaged.
The pending file is the loudest problem, but it is not the most urgent. Pending sectors cluster on weakening drives, and the drive's remaining life is unknown — so back up or clone all the healthy data first, starting with what you cannot replace. Work around the stuck file, not through it: copy folder by folder, skip the casualty for now, and get everything else to safety while the drive still cooperates. Only with the rest secured should you spend drive-hours attacking the stuck file. Technicians learned this order the hard way: drives under rescue attempts die on their own schedule, and whatever was not copied by then is simply gone.
Be clear-eyed about the file itself. The portion of it sitting in the pending sector may already be unreadable — no utility can recover data the head physically cannot read, and software promising otherwise is selling hope. The realistic options, in order:
What never helps: running the same copy twenty times hoping the spot heals. It will not heal; you are only spending the drive.
Once data is safe, the pending sectors force a decision. Writing across the whole surface (a full format, or filling the drive) forces every pending sector to resolve — each either passes its write test or gets reallocated. Then watch: if C5 returns to zero and stays there for months, with C5's neighbour 05 flat as well, the drive caught a small patch of damage and contained it — usable for unimportant storage with monthly checks. If pending sectors reappear, or the reallocated count starts climbing, the surface is failing progressively and no format changes that. Retire the drive. A pending count is the drive asking a question; the weeks after clearing it are where it answers.
Watch the video to see how failed and corrupted copies fit into the full hidden-fault diagnosis.
▶️ Watch Full VideoBecause the damage is physical and fixed in place. A pending sector is one specific patch of the disk surface. Every copy reaches that patch at the same point in the file, the drive retries reading it the same way, and the copy stalls or fails at the same percentage. Random failures suggest software or connection trouble; a failure that repeats at one exact spot is the surface itself.
The sector can be resolved, not healed. When data is written to that spot, the drive retests it: pass, and the sector returns to use; fail, and it is permanently retired and replaced by a spare sector, raising the reallocated count. A full format forces this test everywhere. What cannot be fixed is data already lost inside an unreadable sector — that is why backups come before any of this.
Any number above zero deserves attention, but the trend decides the verdict. A few pending sectors that clear after a rewrite and never return over months of checks are contained damage. Pending sectors that keep reappearing, or that convert into a rising reallocated count, mean the surface is actively failing — replace the drive. Judge by movement over weeks, not by one reading.