Hard Drive Inspector is a monitoring tool that analyzes your drive's S.M.A.R.T. (Self-Monitoring, Analysis, and Reporting Technology) data, warning you of potential problems before they get too serious.
Is your drive overheating, for instance? Normally there's no way to tell, but temperature is one of the values recorded by S.M.A.R.T., and Hard Drive Inspector will display this in your system tray. If the drive's temperature begins to increase over time then this could indicate a crash isn't too far away, but the advance warning should give you the time you need to back up anything important.
Switch to Advanced View and the program will give you an in-depth look at many S.M.A.R.T. attributes: spin-up time, error rates, power cycle counts, reallocated sector counts and more. This didn't seem quite as useful as other S.M.A.R.T. monitors we've seen - Hard Drive Inspector detailed only 20 attributes, and five of those were listed as "Unknown" - but it covers the basics and provides enough detail to reveal upcoming problems.
If you prefer to keep life simple, though, you can just view the program's Health Summary page, which provides the core details you need: drive free space, powered-on time, and numeric values for reliability, performance and error resistance. It's a clear display, and comes at very little cost in terms of system resources, with Hard Drive Inspector consuming less than 2MB of RAM on our test PC.
Version 4.19 adds support for WD My Book Studio II external drives