Temporary files are exactly what the name says, files Windows and your apps needed for a moment and never came back for. Update leftovers, installer caches, thumbnails, browser caches, crash dumps. On a machine that's a year or two old, they quietly add up to tens of gigabytes. Windows can remove most of them, but the controls are scattered across Settings, a dialog that predates Windows XP, a hidden folder, and every browser separately. This guide walks all four, in the order that recovers the most space with the least risk.
Prefer it done for you? eclean's Cleaner runs this whole sweep as one scan, grouped by browsers, apps, Windows, and games, with a preview before anything is removed. It's free, with no trial timer. Download eclean for Windows.
1. Start in Settings, the safest route
Open Settings → System → Storage and click Temporary files. Windows scans for a moment, then shows a checkbox list with the size of each category.
Most entries here are safe by design, because Windows only offers what it can rebuild or no longer needs:
- Temporary files and Temporary Internet Files are app and system scratch space.
- Thumbnails is the cache of little preview images in File Explorer. Safe to clear, but folders full of photos will load their previews slowly once while it rebuilds.
- Delivery Optimization Files are update pieces Windows kept in case another PC on your network wanted them.
- Recycle Bin counts as temporary here too. Check it only if you're sure nothing in the bin still matters.
One entry deserves real caution, Downloads. In this list it means the entire contents of your Downloads folder, not some cache. Leave it unchecked unless you have genuinely sorted that folder out.
Select what you want gone and click Remove files. If you want this to happen on its own, the Storage Sense toggle on the same Storage page clears temporary files and old Recycle Bin contents on a schedule.
2. Disk Cleanup for the system-level leftovers
The Settings page doesn't reach everything. Press Start, type "Disk Cleanup", and open it (it's the old cleanmgr tool, still doing real work). Pick drive C: if asked, then click Clean up system files to rerun it with administrator rights. That second pass unlocks the categories that matter:
- Windows Update Cleanup is old copies of updated system files. It's frequently 5–10 GB and regrows with every patch cycle, which makes this dialog a repeat destination.
- Previous Windows installation(s) appears after a feature update and can hold 20–30 GB. It deletes itself after ten days, but you don't have to wait.
- Windows upgrade log files and Device driver packages are small most of the time, occasionally not.
Check what you want, click OK, then Delete Files. If your drive is critically full rather than just cluttered, work through the full C: drive triage guide instead, which covers the bigger recoveries like the hibernation file and moving games off the drive.
3. Empty the %temp% folder
Apps write scratch files to a per-user Temp folder and rarely clean up after themselves. Press Win + R, type %temp%, and press Enter. You're now in C:\Users\<you>\AppData\Local\Temp.
Press Ctrl + A to select everything, then Delete. Some files will refuse because a running app owns them right now. In the File In Use dialog, tick Do this for all current items and click Skip. That refusal is the safety mechanism, because anything Windows lets you delete here is no longer in use.
There's a second temp folder at C:\Windows\Temp for system-level scratch files. Same routine, but it asks for administrator permission. Skip anything that resists.
Both folders start refilling immediately. That is normal and fine. The point is clearing the months of buildup, not keeping them empty.
4. Clear browser caches
Browsers keep their caches to make pages load faster, so this is less about routine cleanup and more for when the cache has grown huge or a site is misbehaving.
In Chrome, Edge, or Firefox, press Ctrl + Shift + Delete to open the clear-data dialog. Set the time range to All time, select only the cache option (Chrome and Edge call it Cached images and files), and clear. Leave cookies, passwords, and history unchecked unless you specifically want them gone. Clearing cookies signs you out of every site you use.
The cache regrows by design. Clearing it buys back space once, at the cost of slower first loads for a while.
Browsers aren't the only apps with private caches. Game launchers, chat apps, and video tools keep their own, often gigabytes deep, and each hides the clear button somewhere different in its settings. Sweep them when a specific app's folder shows up large in the Storage breakdown, not as a routine.
5. What's safe, and what Windows needs back
A short honest summary, because "delete all temp files" advice online often goes too far:
Safe to delete: everything the Settings Temporary files page offers (except the Downloads entry), everything Disk Cleanup offers, the contents of both Temp folders, browser caches.
Regrows on purpose: thumbnails, Delivery Optimization files, browser caches, both Temp folders. Deleting them costs nothing permanent, but re-deleting them weekly buys you little.
Leave alone: the C:\Windows\Prefetch folder (clearing it is an old myth that makes app launches slower, not faster), C:\Windows\WinSxS (looks huge, is mostly hard links, and Disk Cleanup's Windows Update Cleanup entry is the only safe way to trim it), and pagefile.sys or hiberfil.sys (managed by Windows, not clutter).
Keep it this way without the ritual
The full manual pass touches Settings, Disk Cleanup, two hidden folders, and every browser you use, and the clutter starts rebuilding the same day. Cleaner does the same sweep in one scan, shows you exactly what it found and how much space each category frees before anything is removed, and Pro can run it on a schedule so the buildup stops being your job. Download eclean free. The core stays free for good.
