Your disk is almost full
Windows keeps warning me that my disk is full. What can I safely delete?
Written by The CommonFixes team · fact checked by CommonFixes review desk
Last updated
Short answer
Temporary files, old updates and downloads quietly take tens of gigabytes. You can clear all of them without touching a single document. The quickest thing to try first: run storage sense — Open Settings, System, Storage. Windows shows exactly what is using space and offers Temporary files, which is always safe to clear. Most people are done in about 15 minutes.
Full walkthrough below: 4 steps for Windows and Mac, rated easy.
Sounds like this
- •Red bar on the C drive
- •Cannot save new files
- •Updates refuse to install
Why it happens
Temporary files, old updates and downloads quietly take tens of gigabytes. You can clear all of them without touching a single document.
Work through these in order
0% done- 1
Run Storage Sense
Open Settings, System, Storage. Windows shows exactly what is using space and offers Temporary files, which is always safe to clear.
- 2
Remove the old Windows installation
In the same Temporary files list, tick Previous Windows installations if it is offered. It frees around twenty gigabytes and only removes your ability to roll back an old update.
- 3
Empty the recycle bin and the downloads folder
Sort Downloads by size and delete the installers you already used. They are the easiest large files to lose without regret.
- 4
Move photos and videos off the drive
Copy large folders to an external drive or cloud storage, confirm they opened correctly from the new place, and only then delete the originals.
If none of that worked
If space fills again within days, a backup tool or a sync folder is duplicating files. Check its settings before buying a bigger drive.
Did this fix work for you?
A quick thumbs up helps other readers find the guides that actually work.
Share this fix
Related fixes worth reading
Chosen automatically from the 157 guides on CommonFixes, based on how closely they match this problem.
The drive is full but you cannot see what is using it
Windows says my disk is full but my files are small. Where did the space go?
The drive is full and warnings keep appearing
My C drive is full but I do not know what is using the space.
New drive is not initialised
Why does Windows say my new hard drive is unknown and not initialized?
USB drive shows 0 bytes and will not format
How do I fix a USB flash drive that shows 0 bytes, RAW format and cannot be formatted?
A drive asks to be formatted
My flash drive says you need to format the disk before you can use it. Are my files lost?
Show file extensions in File Explorer
How do I get file extensions to show in File Explorer?
Still not it? Browse every fix or see more in files and storage.
Who wrote this and how we checked it
The CommonFixes team
Writer and researcher
We are a small group of people who spend our days repairing laptops and desktops for family, friends and small offices. Every guide here starts with a problem someone actually brought to us, and we only write down the steps that put the machine right.
- Everyday repairs
- Windows and Mac
- Plain language
CommonFixes review desk
Technical editor
Before a guide goes live, a second person walks through it on a real machine and checks each instruction against the maker's own support pages. Anything we cannot confirm is removed rather than guessed at.
- Fact checking
- Safety warnings
- Source links
This guide was last updated on 10 August 2026. If a step no longer matches what you see on screen, tell us on the contact page and we will test it again.
A gentle reminder: back up anything you cannot afford to lose before major repairs. If a step ever feels risky, stop and ask a technician. There is no shame in that.