I found Windows.old folder (23 GB) on my system drive after the recent major Windows 10 update. I haven't recently installed a new operating system, I moved to Win 10 a year ago and I did a fresh install.
Can the folder be created after Windows updates and can I safely delete to save disk space?
Windows 10 – Windows.old Folder After Anniversary Update
windows-10-v1607windows.old
Related Solutions
The Windows subsystem for Linux (WSL) is still in its beta stage. This feature doesn't come pre-built, so you need to enable it. For this firstly you need to switch to developer mode.
To enable the new Developer features, do the following:
Tap on the Windows-key, type Settings and load Settings - Modern application when the search results are displayed. Switch to Update & Security > For developers to display the new features. There you may Enable "developer mode".
Then enable Bash in Windows features.
Go to Turn on/off Windows features and select Windows Subsystem for Linux from the list. Once you have done that restart your PC.
Then search for Bash or open your cmd and type bash. Now it will ask you to download the Windows subsystem for Linux. Press "y". It will take some time to download the necessary files. Once it's finished, Bash on Ubuntu on Windows will prompt to create a default Linux user on first run. This user:
- Does not need to have the same username as the Windows signed-in user and is treated as a distinct entity from the Windows user account.
- Will be prompted for a new password. The password will be used for Linux commands such as sudo and not used by any system outside of WSL.
- Will be automatically added to the sudo group.
- Will be signed-in automatically for every Bash instance.
- Will not require a password when launching WSL.
Each Windows user has a unique WSL instance. This means all changes made within the WSL environment are unique to that Windows user. This includes Bash users created with the adduser command.
First a warning : Windows.old is almost totally deleted after 28 days,
so better hurry if you wish to recover any data.
This folder is created during a major upgrade of Windows, and allows the rollback to the previous version of Windows.
Here is what Microsoft says :
A custom install is similar to a clean install, but instead of wiping the hard disk clean, your previous Windows installation is moved to a folder called
Windows.old.Windows.oldis an archive of your old Windows installation. It is created by setup for a number of reasons depending on how the upgrade was initiated, including recovery of personal data or to facilitate the rollback to that previous version of Windows if you performed an in place upgrade.
In particular, you will find :
- The old registry hives in
C:\Windows.old\System32\config - Your personal profile files in
C:\Windows.old\System32\Users, which includes Cookies, Start Menu, UserData and more.
For more information see the Microsoft article :
Recover personal files from the Windows.old Folder such as Documents Pictures and Windows Live Mail Emails in Windows 10
Best Answer
The Windows.old folder contains the files from previous OS or version, and is used when the user wants to rollback to the previous OS or Windows 10 version. This folder automatically clears in ~30 days after you upgrade to Windows 10.
If the folder was created when you installed version 1607 (Anniversary Update), the folder might be removed automatically in 10 days.
If Windows doesn't clear the
Windows.oldfolder for some reason, you may remove it it manually using Disk Cleanup (cleanmgr.exe- run as administrator), and clearingPrevious Windows installationfiles.Recovering data from Windows.old
If you find some of your settings are lost after upgrade, you should be able to recover the program specific data files from Windows.old (ProgramData and AppData folders). Move everything you need, to a different folder outside Windows.old before clearing it out.