How to Fix .NET Framework 3.5 Installation Error 0x800f0954 on Windows 11

If you’ve tried enabling .NET Framework 3.5 on your Windows 11 PC—either to run an older app or a specific tool—and suddenly got this frustrating message: “The changes couldn’t be completed. Error code: 0x800F0954”

You’re not alone. This is one of the most common installation errors that appear when Windows can’t download or enable .NET 3.5 correctly.

In this guide, we’ll explain what causes the 0x800F0954 error, and walk you through every proven way to fix it—from enabling group policies to offline installations.

What Causes the 0x800F0954 Error?

The error code 0x800F0954 usually appears when Windows fails to access Microsoft’s update servers to download .NET 3.5 files. Here’s why that might happen:

• Your PC is connected to a domain or managed by Group Policy (WSUS) that blocks updates.
• Windows Update access is disabled or restricted.
• System Component Store (WinSxS) is corrupted or incomplete.
• You tried to install .NET 3.5 offline, but the source files are missing or invalid.

The good news? Every one of these issues can be fixed easily.

Fix 1: Enable the Correct Windows Feature via Command Prompt

Let’s start with the simplest method—manually enabling .NET 3.5 using the DISM tool.

1. Open Command Prompt as Administrator.
   • Press Windows + S, type cmd, then click Run as administrator.
2. Type the following command:
   DISM /Online /Enable-Feature /FeatureName:NetFx3 /All /LimitAccess /Source:D:\sources\sxs
   • Replace D: with the drive letter of your Windows 11 installation media (USB or ISO).
3. Press Enter and wait for Windows to install the feature.

If the process completes successfully, restart your PC and the error should disappear.

Fix 2: Use Windows Features Dialog

If you prefer the GUI method:

1. Press Windows + R and type: optionalfeatures
2. In the Windows Features window, check:
   ✅ .NET Framework 3.5 (includes .NET 2.0 and 3.0)
3. Click OK and wait for installation.

If you again see Error 0x800F0954, continue with the Group Policy fix below.

Fix 3: Bypass WSUS Server Using Group Policy Editor

If your PC is connected to a corporate domain or managed environment, Windows might be configured to download optional components only from a WSUS (Windows Server Update Service)—which often blocks .NET Framework files.

1. Press Windows + R, type gpedit.msc, and press Enter.
2. Navigate to: Computer Configuration → Administrative Templates → System
3. Double-click Specify settings for optional component installation and component repair.
4. Set it to Enabled.
5. Check both boxes:
   • ☑ Contact Windows Update directly to download repair content
   • ☑ Repair content and optional features directly from Windows Update instead of WSUS
6. Click Apply → OK, then restart your PC.

Now, retry enabling .NET 3.5—it should install without the 0x800F0954 error.

Fix 4: Use Registry Editor to Bypass WSUS (If Group Policy Not Available)

Windows Home Edition doesn’t include Group Policy Editor, but you can change the setting directly in the Registry. Be careful while editing the registry. Back it up first via File → Export.

1. Press Windows + R, type regedit, and hit Enter.
2. Navigate to: HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\WindowsUpdate\AU
3. Find the key named UseWUServer.
   • Double-click it and change its value from 1 to 0.
   • If it doesn’t exist, right-click the blank space → New → DWORD (32-bit) → name it UseWUServer → set value = 0.
4. Close Registry Editor.
5. Restart the Windows Update service by running these commands in CMD (Admin): net stop wuauserv net start wuauserv
6. Try installing .NET Framework 3.5 again.

Once installation completes, you can revert the key to its previous value (1) if your system requires WSUS.

Fix 5: Install .NET 3.5 Offline from Windows ISO

If you don’t have internet access—or Windows Update keeps failing—you can install .NET Framework 3.5 manually from a Windows 11 ISO file.

1. Mount your Windows 11 ISO image by right-clicking it → Mount.
   • Note the drive letter assigned (e.g., D:).
2. Open Command Prompt as Administrator.
3. Run: DISM /Online /Enable-Feature /FeatureName:NetFx3 /All /Source:D:\sources\sxs /LimitAccess
4. Wait for the process to complete.

When finished, you should see: “The operation completed successfully.”

Now .NET 3.5 is installed and ready to use—no internet required.

Fix 6: Repair Windows Component Store

If all else fails, your system component store might be corrupted. Repair it using the DISM and SFC tools.

1. Open Command Prompt (Admin).
2. Type the following commands one by one: DISM /Online /Cleanup-Image /RestoreHealth sfc /scannow
3. Wait for both scans to finish.
4. Restart your PC and attempt the installation again.

This ensures all system components (including optional ones like .NET 3.5) can be installed correctly.

Fix 7: Check Windows Update and Reboot

Sometimes, all you need is a fresh update cycle.

1. Go to Settings → Windows Update.
2. Click Check for updates and install any pending updates.
3. Reboot your computer.
4. Try enabling .NET 3.5 again via Windows Features or CMD.

Wrapping Up

The .NET Framework 3.5 Installation Error 0x800F0954 on Windows 11 usually happens because Windows can’t reach Microsoft’s servers or is locked to a corporate update policy.

By enabling the optional feature through Group Policy, modifying the registry, or installing it offline via DISM, you can resolve the error permanently.

Once installed, your legacy apps and tools will run smoothly again — no more “.NET Framework required” pop-ups.