This is from my thinkpad t450s which has a Samsung 240GB SSD. It has been running fine (and still is). But I suddenly noticed one morning that my D: drive had filled up overnight. This is a surprise because I hardly do anything to occupy disk space other than browsing the web, and reading pdfs.
D: drive is 110 GB in size and in MyComputer it shows that 87.9 GBs of it has been used. But when I go into the drive in windows explorer, select all files and folders and then do a file size query it shows that the total size occupied by files and folders is 24.2 GB (there's no change of this even if I select hidden folders, system folders etc). Page file is disabled on the D: drive and the only one on C: drive is system managed. I have also disabled system restore on all partitions.
Surprisingly the disk usage is only abnormal as such in D: drive only. I have checked with WinDirStat, it shows up usage as 24.2 GB. But when run with CCleaner it shows file usage of 87.9 GB and describes the ~60 GB of unexplained usage as "other files".
My question is how can I find this mysterious disk usage/bloat that Windows Explorer cant see and only CCleaner classifies as 'other files' ? Is this a sign of disk wear with some random corrupted bit sectors ? I have checked SSD health and SMART data with software and almost all of them showed no signs of errors or warnings.