I removed an old hard drive from a computer that had been stored away and connected it through an external enclosure. Windows prompted me to run a disk check, and after roughly 12 hours it was only around 15% complete. The drive is fairly large and nearly full, and it has been used since the early 2010s for Windows and other files. Could the slow progress simply be due to the amount of data, or does it suggest the drive is failing? Is it safe to cancel the check? Also, after canceling, Windows reports "Access denied" when I try to access the files or change ownership, even from the command line on Windows 7.
3 Answers
The amount of stored data alone does not necessarily make a scan dramatically slower; the drive’s capacity, connection speed, filesystem condition, and any read errors matter more. USB enclosures can make the process particularly slow. Avoid writing to the drive, and check SMART or run a diagnostic tool before deciding whether it is healthy.
If Windows reports access denied, the files may still be owned by the old Windows installation. An administrator can usually take ownership and grant the current account access through the drive’s Security settings, though Windows 7 may require disabling simple file sharing or using an elevated command prompt. If the disk is failing, fix the data first rather than repeatedly changing permissions or running repair scans.
A disk check can take many hours, especially on a large, nearly full drive connected through a slower USB enclosure. However, extremely slow progress can also happen when the drive is repeatedly retrying bad or unreadable sectors. Check the drive’s SMART health data with a utility such as CrystalDiskInfo, assuming the enclosure passes SMART information through. If the data matters, prioritize copying it to another drive before doing more repairs.
I eventually canceled the check, but Windows now says access is denied and I can’t change the drive’s ownership, even from the command line. I’m using Windows 7.