9 Ways to Fix a Low Disk Space Warning in Windows 10 and 11

Windows throws a “Low Disk Space” notification when your system drive, usually C:, starts running low on free space — the exact threshold isn’t fixed and can vary by drive size and other conditions, but it’s typically somewhere in the single-digit-to-low-double-digit gigabyte range. Clearing temporary files and enabling Storage Sense can recover that space in minutes; if cleanup alone isn’t enough, the fixes below go all the way to resizing the partition.

Fix #1: Delete temporary files via Storage settings

Temporary files, delivery optimization leftovers, and thumbnail caches can quietly add up to several gigabytes — sometimes more on a system that hasn’t been cleaned in a while. This is the fastest place to start.

1. Press Windows + I to open Settings.
2. Go to System > Storage.
3. Click Temporary files.

4. Check the boxes next to Temporary files, Thumbnails, Delivery Optimization Files, and Recycle Bin. These are safe to delete for most people.
5. Review Downloads before checking it. That’s your actual Downloads folder, not a temp location.
6. Click Remove files and confirm.

If the category breakdown doesn’t give you enough detail, a free disk space analyzer like TreeSize Free can show you exactly which folders are eating the most room, useful for tracking down bloated game caches or VM images.

Fix #2: Enable and run Storage Sense

Storage Sense runs cleanup automatically on a schedule, so the warning is less likely to keep coming back.

1. Press Windows + I to open Settings.
2. Go to System > Storage.
3. Under Storage management, toggle Storage Sense to On.
4. Click Storage Sense to open its settings.
5. Under Run Storage Sense, pick During low free disk space or a schedule. Every week is a reasonable default.
6. Turn on Delete temporary files that my apps aren’t using.
7. Set the Recycle Bin cleanup to 14 or 30 days.
8. Scroll down and click Run Storage Sense now to perform an immediate cleanup. The button label may read slightly differently depending on your Windows build.

Fix #3: Use Cleanup recommendations (Windows 11 only)

Windows 11 adds a Cleanup recommendations section that surfaces large unused files, cloud-synced content, and unused apps in one guided view. Windows 10 doesn’t have this section, skip to Fix #4 if you’re on Windows 10.

1. Press Windows + I to open Settings.
2. Go to System > Storage.
3. Click Cleanup recommendations.
4. Expand each section: Temporary files, Large or unused files, Files synced to the cloud, and Unused apps.
5. Check the items you want to address in each section.
6. Click Clean up within each section to remove or offload the selected items.

Files listed under “synced to the cloud” aren’t permanently deleted; they’re made online-only in OneDrive. They’re still accessible; Windows just stops keeping a local copy.

Fix #4: Uninstall large or unused apps

A few unplayed games or old creative suites can account for 20–50 GB. Sorting by size makes the candidates obvious.

Windows 11:

1. Press Windows + I to open Settings.
2. Go to Apps > Installed apps.
3. Click the Sort by dropdown and choose Size (large to small).
4. Find apps you no longer use. Click the three-dot menu next to any app and select Uninstall.

Windows 10:

1. Press Windows + I to open Settings.
2. Go to Apps > Apps & features.
3. Click Sort by and choose Size.
4. Click an app you want to remove and select Uninstall.

Fix #5: Move personal files to another drive

Videos, photos, and downloads are often the real culprits, and there’s no reason they need to live on C:. Moving them frees space without deleting anything.

1. Press Windows + E to open File Explorer.
2. Navigate to your Videos, Pictures, or Downloads folders under This PC.
3. Select the files or folders you want to move, right-click, and choose Cut.
4. Navigate to your target location, a second internal partition or an external hard drive, and paste them there (Ctrl + V).

To make Windows save new files there by default going forward:

1. Press Windows + I to open Settings.
2. Windows 11: Go to System > Storage > Advanced storage settings > Where new content is saved.
3. Windows 10: Go to System > Storage, then click Change where new content is saved.
4. Change the default locations for documents, music, pictures, and videos to your second drive.

A portable external SSD is the quickest option here, plug it in, cut your media library over, and you’re done.

Fix #6: Make OneDrive files online-only

If you use OneDrive, it keeps local copies of synced files by default. Making them online-only removes the local copy while keeping the file fully accessible in the cloud.

1. Press Windows + E to open File Explorer.
2. Navigate to your OneDrive folder in the left sidebar.
3. Right-click a folder, or select multiple files, and choose Free up space.

The file icon changes to a cloud symbol. It’ll download automatically the next time you open it. Nothing is deleted from your OneDrive account.

Fix #7: Disable hibernation to recover several GBs

Windows reserves a file called hiberfil.sys for the hibernation feature. On a machine with 16 GB of RAM, that file can be 10–12 GB. If you use Sleep instead of Hibernate, or you never put the PC to sleep at all, you can reclaim that space entirely.

1. Right-click the Start button and select Terminal (Admin) or Windows PowerShell (Admin).
2. Type the following command and press Enter:

powercfg /h off

3. Restart your PC. The file is gone after the restart.

To re-enable hibernation later, run powercfg /h on the same way.

Fix #8: Run Disk Cleanup (legacy fallback)

Disk Cleanup is the older equivalent of the Storage settings panel, but it still works, and it’s the only built-in place to remove old Windows Update installation files, which can be several GB on their own.

1. Press Start, type Disk Cleanup, and open it.
2. Select drive C: and click OK.
3. Check the categories you want to clear. Temporary Internet Files, Thumbnails, and Recycle Bin are safe choices.
4. To remove old Windows Update files, click Clean up system files, select C: again, and check Windows Update Cleanup.
5. Click OK and confirm.

Fix #9: Resize your C: partition using Disk Management

If your disk has unallocated space or a second partition sitting mostly empty, you can extend C: without any third-party software, provided the free space is directly adjacent to C: on the disk.

1. Right-click Start and select Disk Management.
2. Locate the C: partition in the lower half of the window. If there’s Unallocated space immediately to its right, right-click C: and choose Extend Volume.
3. Follow the wizard to choose how much space to add, then click Finish.

If the free space isn’t directly adjacent to C:, Windows Disk Management won’t extend it. A reputable third-party partition manager can move and resize non-adjacent partitions, but back up your data before running it, as partition operations carry real risk.

When These Fixes Don’t Work

If you’ve worked through the list and C: still fills up fast, the drive itself may be too small for your workload. A 128 GB SSD can hit its limit quickly once you add a couple of modern games or a video editing project. At that point, cleanup is a temporary fix at best. Swapping in a larger NVMe SSD, or adding a secondary drive to offload data, is the permanent solution.

Keep at least 10–15% of your drive free as a general rule. Windows needs headroom for the page file, temp files, and update downloads. Consistently running at under 5 GB free will trigger the warning notification and cause update failures and performance problems.

Conclusion

Fix #1 (deleting temporary files) and Fix #2 (enabling Storage Sense) clear the warning for most people. If space keeps disappearing, large apps or a media library on C: is usually the reason. Fix #4 and Fix #5 handle that directly. A drive that’s genuinely undersized for your usage isn’t a cleanup problem; it needs a hardware fix.