| Error Code | 0x800f081f |
|---|---|
| Operating System | Windows Server 2022 |
| Problem | Missing source files for .NET Framework 3.5 |
| Quick Fix | Specify source path via DISM or PowerShell |
What is Windows Server 2022 Error 0x800f081f?
Error 0x800f081f on Windows Server 2022 is a common “Source Not Found” issue. It occurs when the operating system tries to install .NET Framework 3.5 but cannot locate the necessary installation files.
Unlike newer versions, .NET 3.5 is not pre-installed on the server’s hard drive to save space. Instead, it relies on Windows Update or external installation media to provide the “Side-by-Side” (SxS) files.
If your server is behind a firewall, lacks internet access, or has Windows Update disabled via Group Policy, the installation will fail with this specific error code.
Step-by-Step Solutions
Method 1: Use DISM with Windows Installation Media
This is the most reliable method. You will need the Windows Server 2022 ISO file or physical media mounted to your server.
1. Mount the Windows Server 2022 ISO (e.g., to drive D:).
2. Open Command Prompt (CMD) as an Administrator.
3. Run the following command (Replace “D:” with your actual drive letter):
dism /online /enable-feature /featurename:NetFX3 /all /source:D:\sources\sxs /LimitAccess4. Wait for the progress bar to reach 100%. Once finished, restart your server.
Method 2: Configure Group Policy for Feature Installation
If you cannot use local media, you must tell Windows to use Windows Update instead of your local WSUS server to download optional components.
1. Press Win + R, type gpedit.msc, and hit Enter.
2. Navigate to: Computer Configuration > Administrative Templates > System.
3. Locate the policy: “Specify settings for optional component installation and component repair”.
4. Set it to Enabled and check the box “Download repair content and optional features directly from Windows Update instead of Windows Server Update Services (WSUS)”.
5. Run gpupdate /force in CMD, then try installing .NET 3.5 via Server Manager again.
Method 3: Using PowerShell
PowerShell provides a quick way to trigger the installation if you have the source files ready in a specific folder.
1. Open PowerShell as Administrator.
2. Execute the following command, ensuring the path points to the SxS folder:
Install-WindowsFeature Net-Framework-Core -source D:\sources\sxs3. If successful, you will see a “Success” result in the console window.