[Solved]: Error while installing .net framework 3.5 | Error code “0x800f081f”

 

Error while installing .net framework 3.5 

Here’s a detailed  steps to enable the .NET Framework 3.5 (NetFx3) feature using the DISM (Deployment Imaging Service and Management Tool) command:

1) Mount the OS ISO on Your System

• First, you need to mount the ISO file that contains the installation files for your operating system (e.g., Windows 10 or Windows Server). This allows your system to access the required files to enable certain features like the .NET Framework 3.5.

How to do this:

• Find your OS ISO file (the file you downloaded or have on your system).

• Right-click the ISO file and select Mount. This will create a virtual drive on your computer.

• The mounted ISO will now show up as a new drive (for example, D: or E: depending on your system).

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2) Open Command Prompt as Administrator

• To run the necessary commands, you’ll need administrator privileges.

How to open Command Prompt as Administrator:

1. Click the Start Menu (the Windows logo).

2. Type cmd or Command Prompt in the search bar.

3. Right-click on Command Prompt in the search results, and select Run as Administrator.

4. If a prompt appears asking for permission to allow changes, click Yes.

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3) Run the Command to Enable .NET Framework 3.5

• Now, in the Command Prompt window, you’ll need to run a specific command to enable the .NET Framework 3.5 feature. This command tells Windows where to find the necessary installation files (from the mounted ISO) and installs the feature.

The command to use is:

bash
Dism /online /enable-feature /featurename:NetFx3 /All /Source:d:\sources\sxs\ /LimitAccess

Breaking it down:

• Dism is the tool used to manage Windows features.

• /online means you're applying this to your currently running Windows system.

• /enable-feature is the instruction to enable a feature on your system.

• /featurename:NetFx3 tells the system you're enabling the .NET Framework 3.5.

• /All ensures all necessary components for this feature are installed.

• /Source:d:\sources\sxs\ points to where the necessary installation files are located. You’ll need to replace d: with the correct drive letter for your mounted ISO. For example, if your ISO is mounted on E:, the command should be:

  bash
  Dism /online /enable-feature /featurename:NetFx3 /All /Source:e:\sources\sxs\ /LimitAccess
  

• /LimitAccess prevents Windows from trying to download any files from the internet and forces it to use only the files from your ISO.

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Once you run the command, the system will start installing .NET Framework 3.5 from the mounted ISO. It may take a few minutes, and when it's done, .NET Framework 3.5 should be successfully installed on your computer.