How to solve the error 0X800F0906 when installing .NET Framework 3.5 on Win8.1

Step 1: Unzip the image file completely to a folder (preferably the root directory of the U disk)

Step 2: Find "cmd.exe" in the directory "C: Windowssystem32", right-click to run as administrator (the purpose of this step is to ensure that cmd has sufficient permissions to perform the required operations and avoid errors due to insufficient permissions), as shown below.

Step 3: Enter the following code in the cmd window: "

Dism /online /enable-feature /featurename:NetFx3 /All /Source:X:sourcessxs /LimitAccess" and press enter.

Note: 1. Here X is the drive letter of the USB flash drive.

2. It is best to directly copy and paste the code within quotation marks to avoid input errors.

3. If you extract the image to a folder on drive D or drive E, you must replace "

Step 4: Wait patiently for the installation to complete.