Hard Drive Space Utilization

[cavuman1]

We're running the latest version of Windows 10 on an ancient decade-old Toshiba Satellite laptop, favored by Paleolithic Luddites. This slow-but-steady machine has suffered zero failures, save for a hard drive which gave up the ghost three years ago. Same was replaced with a 300-Gig model, which has performed satisfactorily. We run CPUID's HWMonitor, mostly to keep an eye on internal operating temperatures, but we pay attention to space utilization on the C drive as well. We also run Windows Resource Monitor to evaluate real time RAM and CPU usage. A full complement of protection software always is activated on our Firefox 68.0.1: uBlock Origin, NoScript, Ghostery, and Privacy Possum.

My question is this: can anyone explain the following rather large differential in C-drive space utilization? Before installation of Windows v.1903, 12% of hard drive space was occupied. Afterward, 20%. Now, out of nowhere, 11%. These are nearly 30-Gigabyte swings! (No data seems to be missing and my wife doesn't surf porn sites as far as I can tell.)

I should add that I run Piriform's CCleaner and Defraggler on a weekly basis, and especially after large software downloads. Running these does not correlate with the rather large differences in hard drive space utilization, however, and I'll be durned if I can find a reasonable explanation.

Anyone have an idea?

- Ed :ok:

[Prop swinger]

A Windows.old (https://www.howtogeek.com/223821/what-is-the-windows.old-folder-and-how-do-you-delete-it/) folder?

[cavuman1]

Mixture - Rich. Throttle - Cracked. Master Switch - On. Ignition - On. CLEAR! Prop swinger, we have a good start! Yours is a very reasonable explanation and fits the timeline of expansion and contraction of hard drive space perfectly. I owe you a big thank you and a bigger cold beer!

- Ed :D

[Tocsin]

Also watch out for Windows 10 reserving a large amount of hard drive space for future updates: https://www.howtogeek.com/425563/how-to-disable-reserved-storage-on-windows-10/

[WingNut60]

1903 has been particularly problematic in installation, especially with older computers.
You may find that 1903 has not yet installed cleanly and may still be trying to resolve installation errors.

[Philoctetes]

I might just add, do not just delete the Windows.old folder directly. Better to run Disk Cleanup and then take the Clean System Files option.

[Mac the Knife]

CCleaner is unnecessary and potentially dangerous. Defraggler is also unnecessary, Win10 does it's own defragging to a schedule when it needs to.

Win10 is, in the main, very stable and can look after itself. The more whizzo supero crap you load it with the less memory you'll have and the greater the chances of trouble.

Mac

[cavuman1]

Excellent advice, Mac! I concur and will uninstall said bloatware. Thank you, Sir!

- Ed