An older program or game requires .NET Framework 3.5, and the installation fails: a "Windows couldn't complete the requested changes" window, error code 0x800F0906, 0x800F081F or 0x800F0907, or a checkbox missing from Windows features. Since Windows 11 26H1, Microsoft has changed how this component is installed: the right method therefore depends first on your Windows version.
Problem
- The "Download and install this feature" window fails.
- An error code is displayed: 0x800F0906, 0x800F081F, 0x800F0907 or 0x800F0922.
- The .NET Framework 3.5 checkbox does not exist in Turn Windows features on or off.
- .NET 3.5 disappeared after a Windows upgrade.
Windows couldn't complete the requested changes.
Windows couldn't connect to the Internet to download necessary files.
Error code: 0x800F0906
First of all: do you really need .NET 3.5?
Microsoft points out that .NET Framework 3.5 dates from 2008. Before installing it, look for an updated version of the program that requires it: many publishers offer a version compatible with .NET Framework 4.8.1 or modern .NET, which does not need this component.
Observe before acting
Press Windows + R, type winver and note the version and build number.
| What you see | Situation | Step |
|---|---|---|
| Build 28000 or higher (Windows 11 26H1 and later) | .NET 3.5 is no longer a Windows component | Step 1 |
| Checkbox present in Windows features | Classic method | Step 2 |
| Error 0x800F0906 | Download from Windows Update impossible | Step 3 |
| Error 0x800F0907 | Policy forbidding the download | Step 3 |
| Error 0x800F081F | Source not found or not matching Windows | Step 4 |
| Error 0x800F0922 | More general component installation problem | Special cases |
Step 1: Windows 11 26H1 (build 28000) and later
When to use it: winver shows build 28000 or higher, or the .NET 3.5 checkbox does not exist in Windows features.
Suggested solution
Starting with Windows 11 26H1 (build 28000), Microsoft states that .NET Framework 3.5 is only available as a standalone installer: it is no longer installed as a Windows component.
- Open the Microsoft page Install .NET Framework 3.5 on Windows 11 and download the installer offered (and, if needed, the language pack).
- Run it, then restart if prompted.
Microsoft specifies that these installers only work with the stated Windows version: do not reuse an old installer found on another website.
Expected result: the program that required .NET 3.5 starts.
Rollback: the component is uninstalled from Installed apps if it appears in the list.
Good to know, according to the Microsoft FAQ: this standalone installer is supported until January 9, 2029, .NET 3.5 is not kept when upgrading to a later version of Windows (it must be reinstalled), and the ASP.NET 3.5, .NET 3.5 Extensibility and WCF activation components have been removed.
Step 2: classic method through Windows features
When to use it: Windows 11 25H2 or earlier, PC connected to the Internet.
Suggested solution
- Open the Start menu, search for Windows features and open Turn Windows features on or off.
- Check .NET Framework 3.5 (includes .NET 2.0 and 3.0), click OK and restart if asked.
- Only check the child items Windows Communication Foundation HTTP Activation and Non-HTTP Activation if a program explicitly requires them.
If a program's window offers Download and install this feature, it is the same operation: it requires an Internet connection.
Expected result: the box remains checked after restarting and the program starts.
Rollback: uncheck the same box, then restart.
Step 3: errors 0x800F0906 and 0x800F0907
When to use it: step 2 fails with one of these codes.
Suggested solution
0x800F0906 means Windows could not download the required files. First check the connection, any proxy or VPN, then try again. On a PC attached to a corporate update server (WSUS), downloading from Windows Update may be redirected: the administrator must then act.
0x800F0907 means a policy forbids downloading from Windows Update.
On a personal PC running Windows Pro, you can check this setting:
- Windows key + R, type gpedit.msc.
- Go to Computer Configuration > Administrative Templates > System.
- Open Specify settings for optional component installation and component repair.
- Choose Enabled and check the option to contact Windows Update directly instead of WSUS; make sure the Never attempt to download payload from Windows Update option is not checked.
- Apply, then in a Command Prompt opened as administrator:
gpupdate /force
- Repeat step 2.
Expected result: the installation finishes without an error code.
Rollback: set the policy back to Not Configured, then run gpupdate /force again.
On a corporate PC, do not change this policy yourself: pass the error code on to the IT department.
Step 4: error 0x800F081F or PC without Internet
When to use it: Windows 11 25H2 or earlier, error 0x800F081F, or a PC that cannot reach Windows Update, and only if you have installation media of the same version as the installed Windows.
Suggested solution
Microsoft warns that a source that does not match the installed Windows version may still install an unsuitable version of .NET 3.5 and leave the system in an unsupported state. A USB drive or ISO of another version (for example a newer one) must therefore not be used.
- Plug in the USB drive or mount the matching ISO (double-click the ISO file) and note its letter, here D:.
- Check that the D:\sources\sxs folder exists.
- In a Command Prompt opened as administrator:
Dism /online /enable-feature /featurename:NetFx3 /All /Source:D:\sources\sxs /LimitAccess
Replace D: with the right letter. If it fails, the details are written to C:\Windows\Logs\DISM\dism.log.
Expected result: the command ends with a success message; restart if asked.
Rollback: uncheck .NET Framework 3.5 in Windows features, then restart.
This command only installs .NET 3.5: there is no need to run other system repairs afterwards.
Special cases
| Situation | What to do |
|---|---|
| Error 0x800F0922 | This code is not specific to .NET: first check that Windows updates install normally. See Windows 11: an update refuses to install (0x800f0922, 0x800f081f, 0x8007000d) (French guide). |
| .NET 3.5 gone after an upgrade | Documented behaviour from 26H1 onwards: reinstall it with step 1. |
| Program requiring ASP.NET 3.5 or WCF activation on 26H1 and later | These components have been removed: ask the publisher for an updated version. |
| The program still shows an error even though .NET 3.5 is installed | The problem may come from another component: note the exact message and reply to the topic. |
Final check
- ☐ winver checked and method chosen according to the build.
- ☐ .NET 3.5 installed (box checked, or standalone installer installed).
- ☐ The program that required it starts.
Sources
- Microsoft Learn: Install .NET Framework 3.5 on Windows 11
- Microsoft Learn: .NET Framework 3.5 on Windows 11 FAQ
- Microsoft Learn: Install .NET Framework 3.5 on Windows
- Microsoft Learn: .NET Framework 3.5 installation errors (0x800F0906, 0x800F081F, 0x800F0907, 0x800F0922)
- Microsoft Learn: Deploy .NET Framework 3.5 by using DISM
Still having the problem?
Reply to this topic with the version and build shown by winver, your Windows edition (Home or Pro), the exact error code, the method you tried, the name of the program that requires .NET 3.5 and whether the PC is managed by a company.