When a 1TB Windows C: drive was almost full, a test of three cleanup utilities revealed that Microsoft’s own tools miss most of the junk that accumulates inside the operating system. The experiment, conducted on a drive with only 4% free space, compared Disk Cleanup, Storage Sense and a free third‑party application called PC Manager.
Disk Cleanup, shipped with Windows since 1998, scans a selected drive and offers to delete temporary files, thumbnail caches, the Recycle Bin and similar items. Storage Sense, accessed via Settings > System > Storage, runs automatically on a schedule and can empty the Recycle Bin, clear Downloads and remove temporary files when disk space is low. PC Manager, a separate download, performs a deeper scan, categorises the results and lets users decide what to delete.
Both Microsoft tools reported the same 1.66 GB of removable space. PC Manager listed 26 GB, but that figure included 15.5 GB of items that were not actually junk, so the real total was closer to 20 GB. Manual measurement confirmed that the drive held about 20 GB of unnecessary files. Disk Cleanup and Storage Sense each identified roughly 8 % of that waste, while PC Manager’s list covered about 90 % of the real junk.
The largest culprits were a 9.25 GB NVIDIA shader cache, roughly 5 GB of Chrome cache spread across four profiles, and 2.2 GB of application crash dumps. None of the Windows tools flagged these, but PC Manager did, along with caches left by developer tools such as Python and Node.js.
Microsoft’s own statements suggest that Disk Cleanup overlaps with Storage Sense, and the test confirms that the two utilities use the same engine and apply identical cautious rules. Storage Sense, however, is designed to run quietly in the background and only activates when free space falls below a threshold. On the test drive, Windows considered 3.9 % free to be “not low” and therefore did not run the cleanup, leaving items from six months ago in the Recycle Bin.
Users can change this behaviour by opening Settings > System > Storage > Storage Sense and selecting a schedule such as daily, weekly or monthly. The Recycle Bin and Downloads thresholds can also be set from 0 to 60 days.
PC Manager proved to be the most thorough of the three. It pre‑selected 8.9 GB of safe-to‑remove items, mainly browser caches, crash dumps and temporary files, while leaving the NVIDIA cache and Python files unchecked so the user could decide. The app also offers a “Manage large files” feature that lists files over 10 MB, helping users spot space hogs. In the test, it identified 238 GB of such files.
While PC Manager is not perfect—its “Boost” prompts can be annoying and some freed space may be reclaimed by caches—it remains a useful tool for monthly deep cleanups. For uninstalling applications, a dedicated uninstaller such as Revo Uninstaller Free can remove leftover files, folders and registry entries that the standard Windows uninstaller often leaves behind. CCleaner, once a popular choice, is no longer recommended due to past privacy concerns and its tendency to become bloatware.
In practice, cleaning a nearly full drive rarely yields dramatic gains. In the test, removing all identified junk increased free space from 4 % to about 6–7 %. To free more space, users should target large media files, games and other heavy applications. PC Manager’s large‑file finder can help locate these before deciding what to delete.
Overall, Windows offers basic tools that work well for occasional use, but a dedicated cleaner like PC Manager provides a more comprehensive solution for keeping a PC’s internal storage tidy.
