When you run an in-place upgrade on Windows 11, you may see that reserved storage grows unexpectedly large, sometimes exceeding 10 GB. This happens because the upgrade process creates temporary system files, driver caches, and recovery images that Windows stores inside the reserved storage partition. The reserved storage area is meant for future updates, but an in-place upgrade can bloat it with leftover data that is never cleaned up automatically. This article explains why reserved storage fills up during an in-place upgrade and provides three methods to reclaim that space.
Key Takeaways: Reclaiming Reserved Storage After an In-Place Upgrade
- Settings > System > Storage > Cleanup recommendations > Previous Windows installation(s): Removes the largest batch of leftover upgrade files from reserved storage.
- Disk Cleanup tool (cleanmgr.exe) > Clean up system files > Windows upgrade log files: Deletes log and temporary files created during the upgrade that are not removed by other tools.
- DISM command (Deployment Imaging Servicing and Management): Safely purges residual driver packages and component store backups that can occupy several gigabytes in reserved storage.
Why Reserved Storage Grows During an In-Place Upgrade
Reserved storage is a portion of disk space that Windows 11 sets aside for updates, drivers, and temporary system files. During an in-place upgrade, the operating system copies the new Windows image, driver packages, and recovery tools into this area. The upgrade process also generates log files, temporary installation files, and a backup of the previous Windows installation in case you need to roll back. These files are placed inside the reserved storage partition, not on the main system volume. After the upgrade succeeds, many of these files remain because Windows does not automatically delete them. The result is that reserved storage can swell from its default size of roughly 7 GB to 15 GB or more, reducing the free space available for your data.
The primary culprits are the previous Windows installation folder, Windows upgrade log files, and cached driver packages from the new build. Each of these can consume 2 to 5 GB individually. The following methods target these specific file categories and return reserved storage to its normal size.
Steps to Clean Reserved Storage After an In-Place Upgrade
Method 1: Remove Previous Windows Installation Files Using Storage Settings
This method removes the largest batch of leftover files from the reserved storage area. You must have administrator privileges.
- Open the Storage settings page
Press Win + I to open Settings. Go to System > Storage. - Launch Cleanup recommendations
Click Cleanup recommendations. This opens a list of file categories that can be safely removed. - Select Previous Windows installation(s)
In the Temporary files section, locate Previous Windows installation(s). This entry typically shows a size between 3 GB and 8 GB. Check the box next to it. - Click Clean up
Click the Clean up button. Windows will delete the old Windows installation folder and associated files. This process may take several minutes. Do not interrupt it.
Method 2: Delete Windows Upgrade Log Files Using Disk Cleanup
The Disk Cleanup tool can remove log files and temporary setup files that the upgrade process creates. These files are often hidden from the Settings interface.
- Open Disk Cleanup
Press Win + R, type cleanmgr.exe, and press Enter. Select your system drive usually C: and click OK. - Scan system files
Click Clean up system files. You will be prompted to select the drive again. Choose the system drive and click OK. Disk Cleanup will scan for additional file categories. - Check Windows upgrade log files
In the Files to delete list, scroll down and check Windows upgrade log files. This entry can be 1 GB to 3 GB. Also check Temporary Windows installation files if present. - Click OK and confirm
Click OK, then click Delete Files to confirm. Wait for the process to finish.
Method 3: Use DISM to Clean the Component Store and Driver Packages
DISM (Deployment Imaging Servicing and Management) can remove superseded driver packages and component store backups that the upgrade may have left behind. Run this command from an elevated Command Prompt or PowerShell.
- Open an elevated Command Prompt
Press Win + X and select Terminal (Admin) or Command Prompt (Admin). Click Yes in the User Account Control prompt. - Run the DISM cleanup command
Type the following command and press Enter:DISM /Online /Cleanup-Image /StartComponentCleanup
This command removes superseded versions of components and can free 1 GB to 3 GB from reserved storage. - Reset the base of superseded components
Optionally, run this additional command to further reduce the component store size:DISM /Online /Cleanup-Image /StartComponentCleanup /ResetBase
This command removes all backup versions of components, which means you cannot uninstall the latest cumulative update. Only run this if you are certain you will not need to roll back recent updates. - Verify the cleanup result
After the command completes, check reserved storage size by going to Settings > System > Storage > Show more categories > System & reserved. The reserved storage value should be lower.
If Reserved Storage Still Shows High Usage After Cleaning
Reserved Storage Stays Above 10 GB After Running All Three Methods
Some driver packages or system restore points may still occupy space. Open Disk Cleanup again, click Clean up system files, and check Device driver packages. This removes outdated driver versions that the upgrade may have cached. You can also delete all but the most recent system restore point: press Win + S, type Create a restore point, select the system drive, click Configure, and click Delete to remove all restore points. This frees space but removes your ability to revert to an earlier restore point.
The Storage Settings Show Reserved Storage as 0 Bytes or Grayed Out
This can happen if the Windows update service is currently downloading or installing a new update. Wait for the update to complete, then restart your PC. If the issue persists, run the Disk Cleanup tool as described in Method 2 and check Delivery Optimization Files, which are cached update files that can consume several gigabytes.
You Cannot Delete Previous Windows Installation Files Because the Option Is Missing
The Previous Windows installation(s) entry disappears automatically after 10 days from the upgrade. If you need to remove these files before the 10-day period, use the Disk Cleanup tool instead. In Disk Cleanup, click Clean up system files and check Previous Windows installation(s). This option works even when the Settings entry is not visible.
Reserved Storage Cleanup Methods Comparison
| Item | Settings Cleanup | Disk Cleanup | DISM Command |
|---|---|---|---|
| Target files | Previous Windows installation | Upgrade log files, temp installation files | Superseded drivers, component store backups |
| Typical space freed | 3 GB to 8 GB | 1 GB to 3 GB | 1 GB to 3 GB |
| Requires admin rights | Yes | Yes | Yes |
| Risk of removing needed files | Low | Low | Medium (cannot uninstall recent updates if /ResetBase is used) |
After applying these three methods, reserved storage on Windows 11 should return to its normal size of roughly 7 GB to 8 GB. To prevent future bloat, run Disk Cleanup with the Windows upgrade log files option after every major feature update. You can also set a reminder to check reserved storage size once a month by opening Settings > System > Storage > Show more categories > System & reserved. If you plan to keep a Windows 11 device for more than two years, consider using a 256 GB or larger system drive to avoid running into disk space issues caused by reserved storage growth over time.