Good app providing a readout of hard disk / SSD S.M.A.R.T. data, plus a little bit more. The last version I have is 5.7 with a creation date of 3/30/21. The dev is generous, usually releasing older versions of the software unlocked for free. If you just need to keep an eye on temps, CPUID HWMonitor can do that, while I often use the portable version of the free Crystal Disk Info for a quick look at S.M.A.R.T. data &/or USB drive temps -- crystalmark[.]info/en/software/crystaldiskinfo/ . Note many motherboard BIOS include the option to check S.M.A.R.T. data & will warn you on startup if there's a problem -- running Hard Disk Sentinel when Windows starts is probably not necessary if that BIOS check is enabled. Also note that a drive's S.M.A.R.T. data may or may not provide a warning of future problems -- plenty of drives have failed with S.M.A.R.T. data showing they were perfect, until they weren't.
When Hard Disk Sentinel runs it'll create a number of files in the program's folder based on the drives it found. If you wanted to use it semi-portably, or convert to a portable app delete those DISKDATA... files, probably along with the unneeded language, help [.chm], & uninstall files. If you just copy the program's folder & run Hard Disk Sentinel without installation it will run, creating a subset of the added files & registry entries you get with a full install. Installing Hard Disk Sentinel will get you an added folder in Users\ [UserName]\ AppData\ Roaming\, & another in Users\ [UserName]\ AppData\ Local\ Microsoft\ Windows Sidebar\ Gadgets\. The registry gets the main Hard Disk Sentinel key in HKLM\ SOFTWARE\ WOW6432Node\, with an uninstall key and a few filename association keys added as well. That said, installation also caused a rewrite of the Component hive in my Win11 VM, so the recorded number of changes is HUGE.