Before you begin. This procedure is general reference information, not professional advice. Equipment varies by manufacturer, model, and year. Always follow the documentation supplied with your equipment — where it differs from this page, follow the manufacturer. Verify that you have the tools, the working conditions, and the ability to do this task safely. If anything is unclear, if the equipment is damaged, or if the task exceeds your experience, stop and use a qualified professional. You are responsible for your own safety and for the outcome. This site accepts no liability for any loss, damage, or injury arising from the use of this information.
Specifications marked unverified could not be traced to a manufacturer source. Do not rely on them — obtain the value from your equipment documentation.
A full drive on Windows is not just a nuisance. It slows the machine down and it can stop Windows updates installing, which is the part that eventually matters. The usual advice is to start deleting things, and that is exactly the wrong order: almost every Windows PC is carrying a few gigabytes of temporary files, update leftovers and unused apps that are not yours and that Windows itself offers to clear. This page does those first, and it only reaches your own photos and downloads at the end, when you are the one deciding.
It follows Microsoft's own consumer documentation as it stood on 29 July 2026, for Windows 11 and Windows 10, and it stays inside the Settings app. There is no registry edit here, no Group Policy and no command line, because Microsoft documents this route for people using their own PC and documents the other routes for administrators. Two numbers this page will not print: how much free space your drive should have, and how much a feature update needs. Microsoft says plainly that the low-space point changes with the size of the disk, so a number here would be a guess dressed up as a fact. What you get instead is where Windows shows you the real figure.
READ THE WINDOWS VERSION ON YOUR PC FIRST.
Menu names change with a Windows update. This page follows the Microsoft documentation for Windows 11 and Windows 10.
MAKE A RECORD OF THE FREE SPACE BEFORE YOU START.
A measurement before the work and a measurement after it show you the result. Windows gives no single number for a low drive.
| Item | Note |
|---|---|
| Windows PC | Sign in to the PC with your own account. |
| External drive or memory card optional | Use this only for the transfer of personal files from the PC. |
| Pen and paper | Make a record of the Windows version and the free space before you start. |
Estimated 2 min
Estimated 3 min to 5 min
No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.
No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.
Estimated 10 min to 42 min
EXAMINE EACH ITEM IN A CATEGORY BEFORE YOU SELECT IT.
Windows selects some items for you. The cleanup removes each selected item permanently.
DO NOT SELECT PREVIOUS WINDOWS INSTALLATION(S) IF YOU CAN STILL RETURN TO YOUR LAST WINDOWS VERSION.
That item is the Windows.old folder. Microsoft gives no method to reverse its removal.
Estimated under a minute
Source: Manage drive space with Storage Sense · tier 1 · accessed 2026-07-29
Source: Manage drive space with Storage Sense · tier 1 · accessed 2026-07-29
Source: Manage drive space with Storage Sense · tier 1 · accessed 2026-07-29
Estimated 3 min to 7 min
Source: Manage drive space with Storage Sense · tier 1 · accessed 2026-07-29
Source: Manage drive space with Storage Sense · tier 1 · accessed 2026-07-29
EXAMINE THE DOWNLOADS FOLDER BEFORE YOU GIVE IT A VALUE.
Storage Sense deletes the files in that folder after the period that you select. That folder can hold your only copy of a file.
THE CLOUD CONTENT SETTING DOES NOT DELETE A FILE PERMANENTLY.
Windows makes the file available online only. Free disk space and a network connection make the file local again.
Estimated 11 min to 48 min
Estimated 2 min to 4 min
This page uses one term for each item and holds it throughout, as ASD-STE100 requires. Equipment sellers and other guides use the names below for the same parts.
Stop if an employer or a school controls your PC. A policy on a controlled PC can lock these settings. A policy can also keep files on the drive for a reason. Speak to your IT administrator.
Stop if Windows continues to show a low disk state after all the sections on this page. The next actions change the operating system. Speak to Microsoft Support.
Stop if you cannot identify a file or a folder. Do not delete it. A file with an unknown function can belong to Windows or to an app.
Stop if the drive fills again in a few days. That behaviour is not a storage problem. Speak to Microsoft Support with your Windows version and your OS build.
This page does not give the steps for a compression of the system drive. It does not give the steps for a reset of Windows or for a new installation. Microsoft documents each of those. Each one is larger than a cleanup, and each one needs a backup first.
We are not going to give you a number, and the reason is that Microsoft does not either. Its Storage Sense article says low free disk space varies depending on disk size and minimum operational thresholds, and points you at the capacity bar in Settings, System, Storage — when that bar turns red, you are in a low disk state on that particular machine. That is a real answer, not a dodge: a rule of thumb like fifteen per cent is somebody's guess that got repeated, and on a 2TB drive it means something completely different than on a 128GB one. Read the bar.
It is safe for your PC and it is not reversible for you, which are two different questions. Windows.old is your previous version of Windows, and Microsoft is explicit that if you delete it you will not be able to go back to that previous version. Microsoft also says it is only listed as a deletable system file for a limited window after an upgrade — fewer than 10 days, in its wording. So the honest test is simple: if the current version of Windows is working fine for you and it has been a while, clearing it frees real space. If you upgraded this week and something is behaving oddly, leave it alone until you are sure.
Not unless you tell it to, and this is the single most useful thing to know about it. Microsoft states that with Storage Sense on at default settings, Recycle Bin content is cleared after a while, but items in your Downloads folder and in OneDrive or any other cloud provider will not be touched unless you set it up to do so. The Downloads folder is the one to think about, because a lot of people use it as a filing cabinet rather than a waiting room. If that is you, leave its setting at Never. Nothing else in the default configuration goes near your personal files.
No. That setting applies to files already synced to a cloud folder like OneDrive, and it removes the local copy while leaving the file in the cloud and still visible in File Explorer. Microsoft is explicit that it will not permanently delete any files and that files can be made locally available again if there is free disk space and network connectivity. The catch is in that second half: you need to be online to open one. Anything you want available on a plane or on a bad connection should be marked Always keep on this device, which Microsoft says is exempt from this setting.
The route Microsoft documents for consumers now is Settings, System, Storage — with Cleanup recommendations for a one-off clear-out and Storage Sense for the automatic version. That is what this page follows, because it is what Microsoft's own consumer article instructs. We are not going to tell you the old tool has been removed from your particular build, because that varies and we have not verified it on your version. If you know the old tool and prefer it, nothing here stops you; the Settings route reaches the same categories of file with a clearer explanation of what each one is.
Two things, and the exact wording helps because Windows uses long labels here. On the Storage page, Advanced storage settings expands to reveal Storage used on other drives, which shows what is filling every drive rather than just C, and Where new content is saved, which is the one that changes the default location for new apps, documents, music, pictures and videos. That second label is what step 40 sends you to. Set a different drive there and Windows stops piling new files onto the system drive in the first place, which is the difference between clearing space once and not needing to clear it again.
Some of it is reserved storage. Microsoft says Windows reserves a portion of the drive for temporary files, caches and other files so that updates can succeed and disk usage stays predictable, and that Windows clears that reserve itself when the device is low on space and needs it — for a Windows update, for example. You can see it under System & reserved by choosing Show more categories on the Storage page. It is doing a job. Trying to reclaim it is how people end up with a PC that cannot install an update.
Because it is not really your laptop, in the sense Windows cares about. Microsoft documents a separate administrator-facing route for Storage Sense — Group Policy, configuration service providers and registry settings — and an organisation can use it to lock the configuration or to require that certain files stay on the machine. If the toggles are greyed out, or the numbers do not change, that is the policy working as designed rather than a fault. This is a question for your IT administrator, and it is one they will be able to answer quickly.
It makes a nearly full drive less of a problem, which is not the same claim. Microsoft's own framing is that if your PC is running out of storage space you may notice slower performance or trouble installing Windows updates — the update half is the concrete one, and a PC that cannot install security updates is a real risk rather than an annoyance. If your machine is slow and the drive is not close to full, storage is probably not your bottleneck, and clearing files will not fix it. Read the capacity bar before you decide which problem you have.
Every specification on this page is traced to one of these sources. Tier 1 is a manufacturer document, a published standard, or a government safety authority. See Standards for the full tiering rule.
Current version 1 · updated 2026-07-29 · next review due 2027-07-29
Corrections to this page are listed in the public corrections log. Reports that are credible and not yet verified are listed in the public errata register, and an open one renders above the step it concerns.
Found an error? A correction with a manufacturer source is applied and logged publicly. You can also write to corrections@fixchecklist.com.
Every step above carries its own report control, which tags the report with that step so a correction reaches the right place. For anything about the procedure as a whole — the order of the sections, a step that is missing, something that did not match your equipment — use this: report something about this whole procedure.