Corrupted system files or restrictive group policies frequently block Windows Update from fetching optional features, resulting in errors like 0x800F0906 or 0x800F081F.
The sxs folder (side-by-side) on your Windows installation media contains the component files for optional Windows features, including the .NET Framework 3.5. You can configure the DISM tool to use this folder as a local source for feature files, bypassing the need to download them from the internet. net framework 3.5 sp1 offline installer
| Error Code | Probable Cause | Solution | | :--- | :--- | :--- | | | Source files do not match the current Windows version, or the DISM command tried to go online. | Ensure your source files (CAB or sxs folder) come from an installation media or catalog exactly matching your Windows OS (version, build, language). Use the /LimitAccess switch in your DISM command to force offline installation. | | 0x800F0922 | Group Policy or corruption issue. | This can occur if a Group Policy is blocking feature installation from non-Microsoft sources. Ensure the "Specify settings for optional component installation and component repair" policy is configured correctly. | | The EXE installer seems to hang or fail | Attempting to run the old dotnetfx35.exe on Windows 10 or 11. | The old EXE is not compatible with modern Windows installation methods. Use the DISM command with a .cab file or an ISO source instead. | | "Access Denied" or "You do not have sufficient privileges" | The command prompt or installer was not run with full administrative rights. | Always right-click on Command Prompt or PowerShell and select Run as administrator . | | Error Code | Probable Cause | Solution
Method 2: Enabling via Control Panel (Requires Original Setup Source Configured) | | 0x800F0922 | Group Policy or corruption issue
Do you have access to the original or ISO file?
Type the following command (replace D: with the actual drive letter of your mounted Windows installation media): DISM.exe /Online /Enable-Feature /FeatureName:NetFx3 /All /LimitAccess /Source:D:\sources\sxs
Depending on your operating system, the offline deployment method changes significantly. Modern Windows versions store these files natively as an on-demand feature, whereas older versions require the standalone executable.